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EAST等离子体边界可见光成像系统研究
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作者 陈明 沈飊 +6 位作者 Shinichiro Kado 陈大龙 张恒 郭笔豪 黄耀 蔡福瑞 肖炳甲 《核聚变与等离子体物理》 CAS CSCD 北大核心 2024年第2期222-228,共7页
设计了一套针对Hα波段的高精度折叠式光学系统用来观察放电过程中等离子体边界特征,该系统在全视场中实现了4mm的分辨率。基于图像局部特征和相机模型,发展了光学等离子体边界重建算法,在EAST上针对高场侧中平面处的等离子体控制点进... 设计了一套针对Hα波段的高精度折叠式光学系统用来观察放电过程中等离子体边界特征,该系统在全视场中实现了4mm的分辨率。基于图像局部特征和相机模型,发展了光学等离子体边界重建算法,在EAST上针对高场侧中平面处的等离子体控制点进行了算法验证,光学重建的控制点随时间的演化与磁平衡重建的结果吻合良好。 展开更多
关键词 east装置 等离子体边界 光学成像
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EAST托卡马克中子与伽马在线监测研究
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作者 李成勋 霍志鹏 +1 位作者 钟国强 胡立群 《核科学与工程》 CAS CSCD 北大核心 2024年第3期711-721,共11页
为了实现对实验型先进全超导托卡马克(Experimental Advanced Superconducting Tokamak, EAST)装置聚变产物中子与γ射线的有效监测,建立了一套核辐射在线监测系统。在装置大厅内外区域共布置13个监测点,根据装置大厅内外辐射强度的差异... 为了实现对实验型先进全超导托卡马克(Experimental Advanced Superconducting Tokamak, EAST)装置聚变产物中子与γ射线的有效监测,建立了一套核辐射在线监测系统。在装置大厅内外区域共布置13个监测点,根据装置大厅内外辐射强度的差异,分别采用探测范围广、时间响应快和探测灵敏度高、工作稳定性强相结合的BF3正比计数管和氩气电离室。脉冲信号经前置放大器、运算放大器、脉冲甄别与成形后送入单片机处理,通过双绞线与以太网的混合组网方式将数据传输到采集机,利用LabVIEW采集软件实现对中子与γ射线实时剂量率及累积剂量的采集与存储。监测数据表明,放电时大厅内中子和γ射线剂量率在短时间快速升高,且距离主机越近剂量率越大。而大厅外辐射剂量率始终处于极低水平,几乎不受脉冲放电的影响。该监测系统满足了EAST托卡马克装置辐射监测需求,确保了人员与周围环境辐射安全,保障了聚变装置安全有效运行。 展开更多
关键词 east 核辐射 中子 Γ射线 监测系统
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基于EAST束发射光谱的中性束衰减特征研究
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作者 李建康 符佳 +8 位作者 向东 吕波 尹相辉 李颖颖 王进芳 傅盛宇 李义超 林子超 路兴强 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第4期945-951,共7页
中性束注入(NBI)是托卡马克装置重要的辅助加热与电流驱动手段,中性原子的离化是决定中性束的加热(能量和粒子沉积剖面)和电流驱动效率的关键环节。通常情况下,利用背景等离子体参数与中性束参数模拟计算快的中性粒子与等离子体的离化,... 中性束注入(NBI)是托卡马克装置重要的辅助加热与电流驱动手段,中性原子的离化是决定中性束的加热(能量和粒子沉积剖面)和电流驱动效率的关键环节。通常情况下,利用背景等离子体参数与中性束参数模拟计算快的中性粒子与等离子体的离化,即中性束沉积过程,进而分析托卡马克中性束加热和电流驱动效果。束发射光谱是高能中性粒子注入等离子体后,与等离子体的电子、离子发生碰撞激发,中性粒子退激发过程中产生的一系列特征谱线,其束发射光谱强度受等离子体密度、温度、束能量、束密度等因素影响,可以利用束发射光谱强度变化研究中性束的衰减特性。在EAST托卡马克上通过实验测量中性束粒子与等离子体碰撞激发的光谱强度,分析得到了中性束在不同等离子体密度以及不同中性束能量下的衰减特性,并采用主动束光谱仿真与数值分析软件(SOS)进行了相应的模拟计算,研究表明实验测量与模拟计算结果两者具有较好的一致性,这验证了通过实验测量束发射光谱获取中性束衰减特征的可行性。 展开更多
关键词 east 束发射光谱 中性束衰减
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EAST装置等离子体放电真空室抽气系统抽速标定及应用
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作者 黄明 元京升 +7 位作者 左桂忠 曹斌 余耀伟 庄会东 陈跃 王勇 徐宏亮 胡建生 《真空与低温》 2024年第3期248-254,共7页
真空系统是聚变装置的重要组成部分,EAST真空系统包括等离子体放电真空室和低温超导真空室。等离子体放电真空室又称内真空室。内真空室抽气系统直接影响装置的粒子排出,关系到高参数等离子体放电获得。EAST装置升级改造后的内真空室抽... 真空系统是聚变装置的重要组成部分,EAST真空系统包括等离子体放电真空室和低温超导真空室。等离子体放电真空室又称内真空室。内真空室抽气系统直接影响装置的粒子排出,关系到高参数等离子体放电获得。EAST装置升级改造后的内真空室抽气系统主要包括主抽管道抽气子系统、偏滤器抽气子系统和低杂波加热系统抽气子系统,整个抽气系统使用了6台分子泵、14台外置低温泵和2套内置低温泵。采用粒子平衡的方法,对内真空室抽气系统各子系统进行了抽速标定。实验结果表明,最佳抽气性能区间在5×10^(-4)~5×10^(-3)Pa,并且随着真空室压力增大或者减小,各子系统的抽气速率均下降。对比改进前后的内真空室抽气系统的总抽速,改进后的最大抽速可达170 m^(3)/s,总体抽气速率提升20%左右。在百秒量级等离子放电参数下,利用标定的抽气速率数据初步评估了燃料粒子的滞留情况。本研究为等离子体放电的壁滞留与再循环控制以及其他相关物理实验开展提供了数据支持。 展开更多
关键词 真空抽气系统 抽气速率标定 燃料粒子滞留 east
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基于JWT的EAST实验数据用户身份和服务权限认证 被引量:2
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作者 申正阳 王枫 任环宇 《计算机应用与软件》 北大核心 2024年第5期327-331,344,共6页
用户身份和服务权限认证已成为身份验证和数据访问安全的重要手段。用户身份认证采用动态令牌技术JWT实现。针对JWT丢失和被截获的问题,提出加密存储、解密使用的策略和IP与JWT绑定机制。根据EAST实验数据和用户的现状,将用户资源划分... 用户身份和服务权限认证已成为身份验证和数据访问安全的重要手段。用户身份认证采用动态令牌技术JWT实现。针对JWT丢失和被截获的问题,提出加密存储、解密使用的策略和IP与JWT绑定机制。根据EAST实验数据和用户的现状,将用户资源划分为二级用户,将服务资源划分为三级资源,采用图数据库Neo4j存储用户和资源之间的权限关系,并提出位图法加速权限认证。实验结果表明,基于JWT的认证方法及其安全策略能够有效解决身份和权限认证的问题。相较于传统的关系数据库存储用户权限,图数据库Neo4j和位图法能有效地提高权限认证效率。 展开更多
关键词 身份认证 权限认 JWT east 图数据库 位图法
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FAR3d程序对EAST上阿尔芬不稳定性识别过程中的应用
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作者 王曦辉 黄娟 +5 位作者 赵海林 JVarela 付静 孙延旭 史唱 王书松 《原子能科学技术》 EI CSCD 北大核心 2024年第1期14-22,共9页
为更好理解EAST实验中的等离子体不稳定性现象,文章从实验和模拟两个角度,对EAST中高βN放电区间的阿尔芬不稳定性现象进行了分析。在实验上,本文使用高频磁探针和电子回旋辐射诊断对不稳定性的频率、位置、环向模数进行判断。在模拟上... 为更好理解EAST实验中的等离子体不稳定性现象,文章从实验和模拟两个角度,对EAST中高βN放电区间的阿尔芬不稳定性现象进行了分析。在实验上,本文使用高频磁探针和电子回旋辐射诊断对不稳定性的频率、位置、环向模数进行判断。在模拟上首次应用了FAR3d程序,识别了在ρ=0.45、频率为87 kHz的主导模式TAE(toroidicity-induced Alfven eigenmode),以及ρ=0.55、频率为62 kHz的次主导模式EPM(energetic particle mode),环向模数均为2,与实验中的测量结果对比在误差范围内基本一致,自洽地识别了不稳定性的类型并且得到了位置与频率信息。在此基础上,对有限拉莫轨道(finite Larmor radius, FLR)效应进行评估。模拟结果显示,在EAST高βN放电区间,FLR效应对识别低环向模数n的不稳定性模式的影响较小。在该放电的模式的识别过程中可关闭FLR以加速计算。FAR3d程序高效的计算能力和精准的模拟结果,可为后续EAST的实验提供指导。 展开更多
关键词 FAR3d 阿尔芬本征模 east 快离子
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EAST 低杂波加热对同向切向中性束碰撞力矩影响的研究
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作者 杨明 张新军 +2 位作者 李新霞 吕波 古敬仁 《核聚变与等离子体物理》 CAS CSCD 北大核心 2024年第1期92-97,共6页
为研究低杂波加热对同向切向中性束注入的束功率沉积和碰撞力矩的影响,基于低杂波加热的实验参数,使用TRANSP程序进行了模拟分析。研究结果表明,当注入功率1.3MW、能量50keV的同向切向束时,随着LHW加热束沉积功率降低,快离子电荷交换损... 为研究低杂波加热对同向切向中性束注入的束功率沉积和碰撞力矩的影响,基于低杂波加热的实验参数,使用TRANSP程序进行了模拟分析。研究结果表明,当注入功率1.3MW、能量50keV的同向切向束时,随着LHW加热束沉积功率降低,快离子电荷交换损失增加20%;离子吸收的功率占总的束沉积功率的比例由45%增加到51%。碰撞力矩与束沉积功率的比值由1.327Nm·MW^(-1)增加到1.457Nm·MW^(-1);等离子体电子温度越高,电荷交换损失和碰撞力矩与束沉积功率比值也越大,而低杂波加热期间的束碰撞力矩保持稳定。 展开更多
关键词 中性束注入 低杂波加热 力矩 east装置
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EAST装置上差分抽气测量系统的设计
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作者 潘浩 黄明 +4 位作者 赵胜波 庄会东 余耀伟 左桂忠 胡建生 《真空与低温》 2024年第3期238-242,共5页
在托卡马克装置运行过程中,装置内壁吸附的杂质粒子会释放到内真空室,影响等离子体的平稳运行。因此需要在放电前对装置进行壁处理清洗。设计了差分抽气测量系统,可以在保持内真空室气体比例不变的前提下降低压力,实现四极质谱仪的正常... 在托卡马克装置运行过程中,装置内壁吸附的杂质粒子会释放到内真空室,影响等离子体的平稳运行。因此需要在放电前对装置进行壁处理清洗。设计了差分抽气测量系统,可以在保持内真空室气体比例不变的前提下降低压力,实现四极质谱仪的正常工作,检测壁处理清洗期间的气体成分。整个设计过程围绕关键部件小流导法兰的流导设计展开,采用粒子平衡法计算得出小流导法兰的设计参数。可以在分子流流态下将待测腔室的气压从10 Pa降低至约0.01 Pa。设计结果为类似高压力条件下气体成分监测设备的设计提供参考。 展开更多
关键词 壁处理 残气分析 east
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EAST托卡马克早期H模实验边界局域模特征的统计分析
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作者 刘程鸿 林新 +5 位作者 丁楠 丁根凡 段莫疑 杨清泉 钟方川 王福琼 《东华大学学报(自然科学版)》 CAS 北大核心 2024年第2期153-159,共7页
为分析EAST托卡马克早期(2010—2014年)高约束运行模式(H模)中边界局域模(ELM)与哪些参数具有强相关性,在验证有效性的基础上,采用主打击点处Dα辐射的相对涨落来定量表征边界局域模幅度,建立EAST托卡马克早期H模下ELM特征数据库。统计... 为分析EAST托卡马克早期(2010—2014年)高约束运行模式(H模)中边界局域模(ELM)与哪些参数具有强相关性,在验证有效性的基础上,采用主打击点处Dα辐射的相对涨落来定量表征边界局域模幅度,建立EAST托卡马克早期H模下ELM特征数据库。统计分析表明,ELM频率随边界安全因子的增大而减小,2010年type-ⅢELM的频率随总加热功率的增大而增大。这与其他装置或2015年以后EAST装置上得到的结果不一致,部分原因是碳杂质水平的变化。碳杂质水平是影响EAST托卡马克早期H模实验中ELM行为的重要因素之一。 展开更多
关键词 east托卡马克 边界局域模 统计分析 碳杂质
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Interdecadal variability of summer precipitation in the Three River Source Region: Influences of SST and zonal shifts of the East Asian subtropical westerly jet 被引量:1
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作者 Yumeng Liu Xianhong Meng +5 位作者 Lin Zhao S-Y.Simon Wang Lixia Zhang Zhaoguo Li Chan Wang Yingying An 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期47-53,共7页
Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the i... Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the influence of the East Asian westerly jet(EAWJ)on TRSR rainfall.A strong correlation is found between TRSR summer precipitation and the Jet Zonal Position Index(JZPI)of the EAWJ from 1961 to 2019(R=0.619,p<0.01).During periods when a positive JZPI indicates a westward shift in the EAWJ,enhanced water vapor anomalies,warmer air,and low-level convergence anomalies contribute to increased TRSR summer precipitation.Using empirical orthogonal function and regression analyses,this research identifies the influence of large-scale circulation anomalies associated with the Atlantic–Eurasian teleconnection(AEA)from the North Atlantic(NA).The interdecadal variability between the NA and central tropical Pacific(CTP)significantly affects TRSR precipitation.This influence is mediated through the AEA via a Rossby wave train extending eastward along the EAWJ,and another south of 45°N.Moreover,the NA–CTP Opposite Phase Index(OPI),which quantifies the difference between the summer mean sea surface temperatures of the NA and the CTP,is identified as a critical factor in modulating the strength of this teleconnection and influencing the zonal position of the EAWJ. 展开更多
关键词 Summer precipitation east Asian subtropical westerly jet Three River Source Region Atlantic-Eurasian teleconnection
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A new species of Bostrychus (Gobiiformes: Eleotridae) from the East China Sea 被引量:1
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作者 Rong-Rong Zhang Kuan Yang +1 位作者 Dian Luo Shao-Xiong Ding 《Zoological Research(Diversity and Conservation)》 2024年第1期82-85,共4页
DEAR EDITOR,Bostrychus,a genus in the family Eleotridae of the order Gobiiformes,was first established by Lacepède in 1801(Buffon,1801).Bostrychus currently contains seven recognized species,including two recent ... DEAR EDITOR,Bostrychus,a genus in the family Eleotridae of the order Gobiiformes,was first established by Lacepède in 1801(Buffon,1801).Bostrychus currently contains seven recognized species,including two recent additions(B.microphthalmos and B.scalaris)described in 2005(Hoese&Kottelat,2005)and 2008(Larson,2008),respectively.The natural range of Bostrychus species extends from East Asia to Australia,with the exception of B.africanus,Steindachner,1879,which is distributed in West Africa(Herre,1946).Among the recognized species,B.sinensis,B.zonatus,and B.africanus are relatively widespread,inhabiting diverse areas from estuaries to freshwater streams,while B.scalaris is only found at a single mangrove site in the Selangor State of Malaysia(Larson,2008).The remaining three species exhibit a high degree of habitat specialization and are highly localized(Hoese&Kottelat,2005):B.microphthalmos inhabits a cave stream in the Maros karst of southern Sulawesi,B.aruensis is confined to freshwater environments in the Aru Islands of Indonesia,and B.strigogenys is found only in freshwater areas in southern Papua New Guinea and Irian Jaya. 展开更多
关键词 east KARST environments
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Relative Impacts of Sea Ice Loss and Atmospheric Internal Variability on the Winter Arctic to East Asian Surface Air Temperature Based on Large-Ensemble Simulations with NorESM2 被引量:1
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作者 Shengping HE Helge DRANGE +4 位作者 Tore FUREVIK Huijun WANG Ke FAN Lise Seland GRAFF Yvan J.ORSOLINI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1511-1526,共16页
To quantify the relative contributions of Arctic sea ice and unforced atmospheric internal variability to the “warm Arctic, cold East Asia”(WACE) teleconnection, this study analyses three sets of large-ensemble simu... To quantify the relative contributions of Arctic sea ice and unforced atmospheric internal variability to the “warm Arctic, cold East Asia”(WACE) teleconnection, this study analyses three sets of large-ensemble simulations carried out by the Norwegian Earth System Model with a coupled atmosphere–land surface model, forced by seasonal sea ice conditions from preindustrial, present-day, and future periods. Each ensemble member within the same set uses the same forcing but with small perturbations to the atmospheric initial state. Hence, the difference between the present-day(or future) ensemble mean and the preindustrial ensemble mean provides the ice-loss-induced response, while the difference of the individual members within the present-day(or future) set is the effect of atmospheric internal variability. Results indicate that both present-day and future sea ice loss can force a negative phase of the Arctic Oscillation with a WACE pattern in winter. The magnitude of ice-induced Arctic warming is over four(ten) times larger than the ice-induced East Asian cooling in the present-day(future) experiment;the latter having a magnitude that is about 30% of the observed cooling. Sea ice loss contributes about 60%(80%) to the Arctic winter warming in the present-day(future) experiment. Atmospheric internal variability can also induce a WACE pattern with comparable magnitudes between the Arctic and East Asia. Ice-lossinduced East Asian cooling can easily be masked by atmospheric internal variability effects because random atmospheric internal variability may induce a larger magnitude warming. The observed WACE pattern occurs as a result of both Arctic sea ice loss and atmospheric internal variability, with the former dominating Arctic warming and the latter dominating East Asian cooling. 展开更多
关键词 Arctic sea ice loss warm Arctic–cold east Asia atmospheric internal variability large-ensemble simulation NorESM2 PAMIP
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The Influence of the Closure of the East Paleo-Tethys Ocean on Southern South China:Evidences from Kinematics and^(40)Ar/^(39)Ar Geochronology of the Rongxian Ductile Shear Zone in Southeastern Guangxi 被引量:1
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作者 HUANG Wenqiang LI Saisai +5 位作者 XIN Liangwei FENG Zuohai ZHANG Hongrui GENG Jieli LIU Kun SHI Chunyan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1125-1140,共16页
The Triassic was a crucial period in the tectonic evolution of the South China Block.Research on tectonic deformation during this period provides information on intracontinental orogenic mechanisms in South China.In t... The Triassic was a crucial period in the tectonic evolution of the South China Block.Research on tectonic deformation during this period provides information on intracontinental orogenic mechanisms in South China.In this study,alongside thermochronological analyses,we examine the macroscopic and microscopic structural features of the Rongxian ductile shear zone,located south of the Darongshan granite in the southeastern part of Guangxi Province,on the southern margin of South China.Sinistral shear is indicated by the characteristics of rotatedσ-type feldspar porphyroclasts,stretching lineations defined by elongated quartz grains and the orientations of quartz c-axes.LA-ICP-MS U-Pb dating of zircons from two samples of granitic mylonite and one of granite yielded ages of ca.256 Ma.Furthermore,two samples of granitic mylonite yield muscovite^(40)Ar/^(39)Ar plateau ages of 249-246 Ma.These results indicate that the Rongxian ductile shear zone resulted from Early Triassic deformation of the late Permian Darongshan granite.This deformation was likely related to the closure of the eastern Paleo-Tethys Ocean and the subsequent collision of the South China and Indochina blocks,during the early stage of the Indosinian orogeny. 展开更多
关键词 ductile shear zone ^(40)Ar/^(39)Ar geochronology TRIASSIC South China Block east Paleo-Tethys Ocean
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EAST准直测量基准控制网升级改造方案的设计及实施
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作者 顾永奇 郑元阳 +2 位作者 袁忠 王俊 魏文琪 《核聚变与等离子体物理》 CAS CSCD 北大核心 2024年第3期290-296,共7页
为了获得更高等离子体运行参数和更长的运行时间,对EAST装置进行了升级改造。介绍了在EAST性能升级改造过程中,准直测量基准控制网改造升级方案。增加了基准点的数量,优化了基准点的布局,采用水准仪和多台站激光跟踪仪对内外基准控制网... 为了获得更高等离子体运行参数和更长的运行时间,对EAST装置进行了升级改造。介绍了在EAST性能升级改造过程中,准直测量基准控制网改造升级方案。增加了基准点的数量,优化了基准点的布局,采用水准仪和多台站激光跟踪仪对内外基准控制网进行多路径测量,并利用SA软件进行统一空间测量网络(USMN)的三维平差分析计算。通过测量数据分析,获得准直测量基准控制网的实测平均测量不确定度为0.039mm,最大测量不确定度为0.176mm,优于设计要求平均测量不确定0.15mm和最大测量不确定度0.20mm,满足了EAST升级改造后新型偏滤器及关键部件的安装需求。 展开更多
关键词 east 准直测量 基准控制网 USMN 测量不确定度
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EAST托卡马克钨杂质上下不对称性分布的实验研究
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作者 赵伟宽 张凌 +9 位作者 程云鑫 周呈熙 张文敏 段艳敏 胡爱兰 王守信 张丰玲 李政伟 曹一鸣 刘海庆 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第3期168-176,共9页
基于EAST托卡马克装置高性能极紫外空间分辨杂质光谱仪,本文首次开展了磁约束聚变装置高Z杂质上下不对称分布的实验研究.实验结果显示,在同向中性束注入期间,等离子体芯部环向旋转速度V_(t0)大,钨杂质上下不对称性较强,且辐射(密度)较... 基于EAST托卡马克装置高性能极紫外空间分辨杂质光谱仪,本文首次开展了磁约束聚变装置高Z杂质上下不对称分布的实验研究.实验结果显示,在同向中性束注入期间,等离子体芯部环向旋转速度V_(t0)大,钨杂质上下不对称性较强,且辐射(密度)较强的一侧背离离子B×▽B漂移方向;当从上外偏滤器充气口注入氘化甲烷气体后,V_(t0)迅速下降,原有上下不对称性发生反转.因此我们针对近似条件下W^(32+)杂质离子特征线辐射不对称因子I_(u)/I_(d)与V_(t0)依赖关系开展了进一步的统计分析.结果表明,I_(u)/I_(d)正相关于V_(t0),当V_(t0)<20 km/s以下时,不对称性发生反转.上述现象从实验角度验证了漂移动理学的理论预测,说明环向旋转带来的离心力影响了杂质离子平行于磁场方向的动量守恒,作为直接诱因,造成了高Z杂质密度的上下不对称分布,进而影响辐射的分布.本文对钨杂质上下不对称性分布的实验观测为进一步开展高Z杂质极向输运的机理研究打下了坚实的基础,并为今后聚变堆高Z杂质控制提供重要的参考. 展开更多
关键词 east托卡马克 杂质上下不对称性 磁场方向 偏滤器充气
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基于改进EAST算法的电气设备铭牌文字检测
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作者 刘彦希 吴浩 +2 位作者 蔡源 唐丹 宋弘 《四川轻化工大学学报(自然科学版)》 CAS 2024年第3期42-50,共9页
针对电气设备铭牌文本检测任务中存在检测效果较差、文本边界框检测不准确等问题,提出一种基于深度学习算法EAST的改进算法,重点优化EAST算法对长文本检测效果较差和小目标遗漏问题。使用ResNet50残差网络代替VGG算法作为EAST算法特征... 针对电气设备铭牌文本检测任务中存在检测效果较差、文本边界框检测不准确等问题,提出一种基于深度学习算法EAST的改进算法,重点优化EAST算法对长文本检测效果较差和小目标遗漏问题。使用ResNet50残差网络代替VGG算法作为EAST算法特征提取的主干网络,同时引入金字塔注意力模块和空洞卷积,增强图像各层特征图的细节信息和彼此间的关联性、扩大特征图的感受野,解决EAST算法存在的缺陷问题。此外,使用Dice、Focal损失建立改进算法的损失函数,对改进模型的训练过程进行优化。结果表明,改进的算法在ICDAR 2015以及自行建立的电气设备铭牌数据集上的召回率和准确率均高于传统EAST算法,召回率平均提升约7.8%,准确率平均提升4.3%,综合性能提升约6.3%。 展开更多
关键词 电气设备铭牌 文本检测 east 特征提取 损失函数
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Physical design and recent experimental results of the new ICRF antenna on EAST
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作者 杨桦 张新军 +7 位作者 袁帅 秦成明 张伟 G.URBANCZYK 钱金平 刘鲁南 王高翔 陈青青 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第6期169-176,共8页
Two new ICRF antennas operating in the ion cyclotron radio frequency(ICRF) range have been developed for EAST to overcome the low coupling problem of the original antennas.The original ICRF antennas were limited in th... Two new ICRF antennas operating in the ion cyclotron radio frequency(ICRF) range have been developed for EAST to overcome the low coupling problem of the original antennas.The original ICRF antennas were limited in their power capacity due to insufficient coupling.The new antenna design takes into account both wave coupling and absorption processes through comprehensive wave coupling and absorption codes,with the dominant parallel wave number k∥of 7.5 m-1at dipole phasing.Through the use of these new ICRF antennas,we are able to achieve 3.8 MW output power and 360 s operation,respectively.The initial experimental results demonstrate the reliability of the antenna design method. 展开更多
关键词 ICRF ANTENNA COUPLING east
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Changes in Calcareous Nannofossil Assemblages and Paleoenvironmental Interpretation of the Early Miocene Lice Formation, Kahramanmara? Basin, Turkey, East Mediterranean
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作者 Caner KAYAÖZER Muazez Esra ORHAN Uğur TEMİZ 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第4期1021-1034,共14页
This study investigated the calcareous nannofossil assemblages in detail from the early Miocene aged Lice Formation outcropping in the Kahramanmara? basin. The biostratigraphy of calcareous nannofossils was outlined a... This study investigated the calcareous nannofossil assemblages in detail from the early Miocene aged Lice Formation outcropping in the Kahramanmara? basin. The biostratigraphy of calcareous nannofossils was outlined and paleoenvironmental features determined. In 81 samples taken from three measured sections in the region, 17 calcareous nannofossil genus and 48 nannofossil species were identified. These calcareous nannofossil genus and species identified the Lice Formation as being in the CNM4 nannofossil biozone. The abundance and diversity of early Miocene calcareous nannofossil species varied in the measured sections, with the samples generally moderate-poor, apart from a few samples. The relative abundance of individuals of Cyclicargolithus floridanus, Coccolithus pelagicus, Reticulofenestra hagii and Sphenolithus moriformis species, with paleoecological importance identified in the study region, indicate that in early Miocene times, the basin in which the Lice Formation deposited was meso-eutrophic with excess nutrient input, temperate and generally stable shallow marine conditions. 展开更多
关键词 PALEOECOLOGY NANNOFOSSIL BURDIGALIAN east Mediterranean
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Factors of Adherence to Concurrent Tuberculosis Treatment and Antiretroviral Therapy among HIV-TB Co-Infected Individuals in the East Region, Cameroon in the COVID-19 Era: A Retrospective Cohort Study
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作者 François Anicet Onana Akoa Ulrich Dama +5 位作者 Jean Ndibi Abanda Alphonse Tedonge Asobochia Melkior Fobasso Dzeuta Pearl Nsom Mbu Yokyu Zachary Pangwoh Pierre Yassa Yoniene 《Health》 2024年第2期131-147,共17页
Context/Objectives: Tuberculosis (TB) and HIV co-infection is a serious health problem in Cameroon. The problems associated with poor adherence to treatment are on the increase worldwide. This problem can be observed ... Context/Objectives: Tuberculosis (TB) and HIV co-infection is a serious health problem in Cameroon. The problems associated with poor adherence to treatment are on the increase worldwide. This problem can be observed in all situations where patients are required to administer their own medication, whatever the type of illness. The general objective of this study was to assess the factors affecting adherence to treatment among HIV-TB co-infected patients in health facilities in the East Region in the COVID context. Method: A retrospective cohort study before and during COVID-19 was conducted in HIV care units in 13 health districts in the East Region of Cameroon. Data were collected using a questionnaire recorded in the Kobo Collect android application, analyzed using SPSS version 25 software and plotted using Excel. Results: The pre-COVID-19 cohort compared to the during-COVID-19 cohort had a 1.90 risk of not adhering to treatment (OR: 1.90, CI {1.90 - 3.37}) and the difference was statistically significant at the 5% level (p-value = 0.029). Frequency of adherence was 65.4% (140/214). Adherence before COVID-19 was 56.9% whereas during COVID-19, it was 74.3%. Conclusion: The implementation of targeted interventions in the COVID-19 context, using evidence-based data and integrating the individual needs of HIV-TB co-infected patients, improved adherence to concurrent anti-tuberculosis treatment and antiretroviral therapy during the COVID-19 Era. 展开更多
关键词 Factors of Adherence Tuberculosis Treatment Antiretroviral Therapy HIV-TB Co-Infection east Region Cameroon
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Real-time data processing method for CO_(2) dispersion interferometer on EAST
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作者 张家敏 姚远 +6 位作者 刘郁阳 储宇奇 阮天翼 张耀 刘海庆 揭银先 凌必利 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第8期121-126,共6页
A real-time data processing system is designed for the carbon dioxide dispersion interferometer(CO_(2)-DI)on EAST.The system utilizes the parallel and pipelining capabilities of an fieldprogrammable gate array(FPGA)to... A real-time data processing system is designed for the carbon dioxide dispersion interferometer(CO_(2)-DI)on EAST.The system utilizes the parallel and pipelining capabilities of an fieldprogrammable gate array(FPGA)to digitize and process the intensity of signals from the detector.Finally,the real-time electron density signals are exported through a digital-to-analog converter(DAC)module in the form of analog signals.The system has been successfully applied in the CO_(2)-DI system to provide low-latency electron density input to the plasma control system on EAST.Experimental results of the latest campaign with long-pulse discharges on EAST(2022–2023)demonstrate that the system can respond effectively in the case of rapid density changes,proving its reliability and accuracy for future electron density calculation. 展开更多
关键词 dispersion interferometer REAL-TIME electron density FPGA east
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