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Experimental study on fast electron generation during internal crash

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Plasma Science and Technology 2021年第4期23卷 30-35页

作者： Chaowei MAI Liqun HU Liqing XU zhengping luo Shiyao LIN Yiping CHEN EAST Team Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China

Hard x-ray(HXR)burst is found during internal crash in the flat top current stage of experimental advanced superconducting tokamak(EAST)discharges and it is caused by fast *** generated electrons during internal crashes may be an operational safety issue in advanced *** an internal crash,locations of fast electron generation from HXR evolution agree with areas of magnetic reconnection from soft x-ray(SXR)tomographic *** statistical analyses show a 27μs time difference between SXR crashes and HXR bursts,and the agreement between time broadening of HXR bursts and estimated characteristic time of magnetic reconnection in *** magnetic reconnections during internal crash are proved to generate fast electrons,by both spatial and temporal agreements.

关键词： EAST internal crash fast electron magnetic reconnection

Fast estimation of ion temperature from EAST charge exchange recombination spectroscopy using neural network

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Plasma Science and Technology 2019年第10期21卷 28-32页

作者： Baoyue CHAI Yingying LI Ze CHEN Wei TAO Yixuan ZHOU Shifeng MAO zhengping luo Yi YU Bo LV Minyou YE Department of Engineering and Applied Physics University of Science and Technology of ChinaHefei 230026People’s Republic of China Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China

Ion temperature, as one of the most critical plasma parameters, can be diagnosed by charge exchange recombination spectroscopy (CXRS). Iterative least-squares fitting is conventionally used to analyze CXRS spectra to identify the active charge exchange component, which is the result of local interaction between impurity ions with a neutral beam. Due to the limit of the time consumption of the conventional approach (~100 ms per frame), the Experimental Advanced Superconducting Tokamak CXRS data is now analyzed in-between shots. To explore the feasibility of real-time measurement, neural networks are introduced to perform fast estimation of ion temperature. Based on the same four-layer neural network architecture, two neural networks are trained for two central chords according to the ion temperature data acquired from the conventional method. Using the TensorFlow framework, the training procedures are performed by an error back-propagation algorithm with the regularization via the weight decay method. Good agreement in the deduced ion temperature is shown for the neural networks and the conventional approach, while the data processing time is reduced by 3 orders of magnitude (~0.1 ms per frame) by using the neural networks.

关键词： CXRS neural network ion temperature EAST

硅化钽/硅化钼基热防护涂层短时高温结构演化

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稀有金属材料与工程 2020年第2期49卷 712-717页

作者：李俊峰罗正平航天材料及工艺研究所北京100076

以硅化钽、硅化钼、硼硅玻璃粉为原料,1200℃短时烧结制备了耐高温热防护涂层。然后采用乙炔焰在1650℃烧蚀涂层2 min,自然冷却至室温。利用X射线衍射、扫描电子显微镜和X射线电子能谱研究了该耐高温热防护涂层在1650℃加热前后的涂层... 详细信息

以硅化钽、硅化钼、硼硅玻璃粉为原料,1200℃短时烧结制备了耐高温热防护涂层。然后采用乙炔焰在1650℃烧蚀涂层2 min,自然冷却至室温。利用X射线衍射、扫描电子显微镜和X射线电子能谱研究了该耐高温热防护涂层在1650℃加热前后的涂层结构和组分变化。结果显示制备出的热防护涂层表面为Ta2O5和少量TaSi2。经过1650℃短时高温烧蚀后,涂层表面烧蚀中心区形成大量片状Ta2O5,该Ta2O5连成片。涂层截面形貌显示高温烧蚀后涂层接近表面部分发生致密化,厚度约23μm。涂层截面的元素面扫描分析显示截面上钽、钼元素分布均匀,即涂层具有良好的结构均匀性。

关键词：硅化钽硅化钼热防护涂层结构演化

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福建省病原真菌分离培养分析

中华皮肤科杂志 1993年第4期26卷 235-236页

作者：施秀明陈永昆 350405 福建医学院附属第二医院

我们自1981年1月~1991年1月先后在泉州,福州,并从闽东、闽西、闽南、闽北等5个地区收取标本进行真菌学检查,结果分析报告如下.

关键词：病原真菌分离培养福建

Magnetic diagnostics layout design for CFETR plasma equilibrium reconstruction

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Chinese Physics B 2024年第4期33卷 537-543页

作者：于庆泽黄耀罗正平汪悦航刘自结芮望颐吴凯肖炳甲李建刚 Institute of Plasma Physics Hefei Institute of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China

Plasma equilibrium reconstruction provides essential information for tokamak operation and physical *** extensive and reliable set of magnetic diagnostics is required to obtain accurate plasma *** study designs and optimizes the magnetic diagnostics layout for the reconstruction of the equilibrium of the plasma according to the scientific objectives,engineering design parameters,and limitations of the Chinese Fusion Engineering Test Reactor(CFETR).Based on the CFETR discharge simulation,magnetic measurement data are employed to reconstruct consistent plasma equilibrium parameters,and magnetic diagnostics'number and position are optimized by truncated Singular value decomposition,verifying the redundancy reliability of the magnetic diagnostics layout *** provides a design solution for the layout of the magnetic diagnostics system required to control the plasma equilibrium of CFETR,and the developed design and optimization method can provide effective support to design magnetic diagnostics systems for future magnetic confinement fusion devices.

关键词： plasma equilibrium reconstruction EFIT code flux loops and magnetic probes optimization

Plasma current tomography for HL-2A based on Bayesian inference

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Plasma Science and Technology 2024年第5期26卷 165-173页

作者：刘自结王天博吴木泉罗正平王硕孙腾飞肖炳甲李建刚 College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060People’s Republic of China Southwestern Institute for Physics Chengdu 610200People’s Republic of China Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China

An accurate plasma current profile has irreplaceable value for the steady-state operation of the *** this study,plasma current tomography based on Bayesian inference is applied to an HL-2A device and used to reconstruct the plasma current *** different Bayesian probability priors are tried,namely the Conditional Auto Regressive(CAR)prior and the Advanced Squared Exponential(ASE)kernel *** to the CAR prior,the ASE kernel prior adopts nonstationary hyperparameters and introduces the current profile of the reference discharge into the hyperparameters,which can make the shape of the current profile more flexible in *** results indicate that the ASE prior couples more information,reduces the probability of unreasonable solutions,and achieves higher reconstruction accuracy.

关键词： plasma current tomography Bayesian inference machine learning Gaussian distribution

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水轮发电机推力轴承支承结构性能的研究

东方电气评论 2000年第3期14卷 142-147页

作者：罗正平东方电机股份有限公司

通过在1000t推力轴承试验台上进行的4种推力轴承支承结构钨金瓦的试验结果的分析与对比,论述支承结构对水轮发电机推力轴承性能的影响。双托盘支承及弹簧束多点支承结构能部分抵消推力轴承运行时产生的力变形与热变形,瓦面形状较佳,具... 详细信息

通过在1000t推力轴承试验台上进行的4种推力轴承支承结构钨金瓦的试验结果的分析与对比,论述支承结构对水轮发电机推力轴承性能的影响。双托盘支承及弹簧束多点支承结构能部分抵消推力轴承运行时产生的力变形与热变形,瓦面形状较佳,具有较大的承载能力,很适合三峡机组推力轴承。

关键词：水轮发电机推力轴承支承结构性能

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对甲苯磺酰氨基脲的合成工艺研究

化学工程 2001年第1期29卷 56-59页

作者：张秋禹马鹏豫罗正平吴旻谢钢西北工业大学化工系西安710072

以甲苯、氯磺酸、水合肼、氰酸盐等为原料 ,通过三步反应合成聚丙烯用高效发泡剂对甲苯磺酰氨基脲。研究表明 ,加入一定量的铵盐可提高制备对甲基苯磺酰氯中间体的反应温度 ,从而使其收率增加 ;用四氢呋喃做溶剂比用苯做溶剂可以得到较... 详细信息

以甲苯、氯磺酸、水合肼、氰酸盐等为原料 ,通过三步反应合成聚丙烯用高效发泡剂对甲苯磺酰氨基脲。研究表明 ,加入一定量的铵盐可提高制备对甲基苯磺酰氯中间体的反应温度 ,从而使其收率增加 ;用四氢呋喃做溶剂比用苯做溶剂可以得到较高产率的对甲基苯磺酰肼中间体 ;反应温度对终产物的收率影响较大。

关键词：发泡剂对甲苯磺酰氨基脲对甲基苯磺酰氯对甲基苯磺酰肼合成工艺

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点焊机器人轨迹能耗模型及其优化算法研究

中国机械工程 2016年第1期27卷 14-20页

作者：邓乾旺罗正平张丽科崔巍湖南大学汽车车身先进设计制造国家重点实验室长沙410082

提出一种点焊机器人最优能耗轨迹优化方法,将机器人关节空间中的关键点用五次多项式曲线连接,并基于机器人动力学建立了永磁交流伺服电机驱动的点焊机器人轨迹能耗模型。在考虑运动学、动力学及生产周期约束的情况下,采用蜜蜂进化型遗... 详细信息

提出一种点焊机器人最优能耗轨迹优化方法,将机器人关节空间中的关键点用五次多项式曲线连接,并基于机器人动力学建立了永磁交流伺服电机驱动的点焊机器人轨迹能耗模型。在考虑运动学、动力学及生产周期约束的情况下,采用蜜蜂进化型遗传算法求解了点焊机器人最优能耗轨迹。为保证算法全局寻优和收敛速度,构建了一种非线性适应度函数。仿真结果表明,与之前算法相比,求解效率更高,且最优能耗轨迹较最短时间轨迹能耗明显减少。

关键词：点焊机器人能耗轨迹规划蜜蜂进化型遗传算法