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Electromagnetic Properties of a New Microwave Plasma Torch with Double Resonance Configuration

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Chemical Research in Chinese Universities 2016年第4期32卷 549-555页

作者： YU Bingwen JIN Wei ZHU Dan ying yangwei YU Haixiang SHAN Jin XU Chen LIU Wenlong JIN Qinhan Research Center for Analytical Instrumentation Institute of Cyber-systems and ControlCollege of Control Science and Engineering Zhejiang University Hangzhou 310058 P. R. China Zhejiang Supcon Research Co. Ltd. Hangzhou 310058 P. R. China

In order to obtain a stable plasma and improve the performance of the torch for atomic emission spectroscopy（AES）, the structure of microwave plasma torch（MPT） was analyzed. The transmission and distribution characteristics of the electromagnetic field of the torch configuration with two or three concentric tubes, as well as the metal spacer between inner and intermediate tubes with different depths were simulated with electromagnetic simula- tion software and verified by experiments. The results indicate that the inner tube of MPT plays an important role in strengthening the electric field intensity at the opening end of the MPT and redistributing the electromagnetic field in the whole torch by forming a double resonance configuration, and contributes to enhancing the macroscopic stability and the self-sustainment of the plasma. The stability of the plasma is proved to be excellent when the metal spacer between the inner and intermediate tubes is located at a place 20-30 mm away from the top opening of the torch. A proper location of the spacer can also avoid the formation of a static filament plasma or a rotating plasma rooted from the outer wall of the inner tube. With the help of morphological analysis, the underlying reason why MPT possesses a great tolerance to wet aerosols and air introduction was clearly made, that is, the formation region of the plasma formed with MPT is apparently separated from the reaction zone of it.

关键词： Microwave plasma torch(MPT) Double resonance configuration Electromagnetic simulation

Development of a Novel Kilowatt Microwave Plasma Torch Source for Atomic Emission Spectrometry

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Chemical Research in Chinese Universities 2017年第5期33卷 709-713页

作者： ZHU Dan JIN Wei YU Bingwen ying yangwei YU Haixiang SHAN Jin YAN Yuwei XU Chen WANG Baolai JIN Qinhan Research Center for AnalyticaI Instrumentation Institute of Cyber-systems and ControlCollege of Control and Engineering Zhejiang University Hangzhou 310058 P. R. China Zhejiang Tracetech Technology Co. Ltd. Hangzhou 310053 P. R. China Hangzhou Steam Turbine Co. Ltd. Hangzhou 310022 P R. China

Traditional low power-microwave plasma torch（MPT） excitation source of atomic emission spectrometry was shown to be good for the introduction of dry aerosols, but poor for wet sample aerosols. In this work, some significant modifications have been made to traditional MPT. A new MPT excitation source working at kilowatt microwave power has been developed. The kilowatt MPT source can sustain stable plasmas with double or even more filaments, presenting a ＂bell＂ form, where the region around the converging point is the optimum region for analysis. The tolerance to aqueous aerosol of the torch is enhanced significantly compared to the traditional one. Therefore, the desolvation system that the low power MPT source has to be relied on can be gotten rid of. A set of favorable detection results have been obtained with direct wet sample aerosol introduction. The kilowatt MPT source is expected to become a practical excitation source for atomic emission spectrometry that will be widely used.

关键词： Kilowatt microwave plasma torch Coupling structure Direct sample aerosol introduction Atomic emis- sion spectrometry

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面形自适应超声在机测厚方法研究

机械工程学报 2018年第18期54卷 11-17页

作者：刘海波廉盟周连杰应杨威王永青大连理工大学精密与特种加工教育部重点实验室大连116024 辽宁重大装备制造协同创新中心大连116024

针对复杂曲面薄壁零件高效、精密在机测厚难题,提出一种面形自适应的超声在机测厚新方法,创新设计多功能高度集成的超声在机测厚装置,进一步建立超声在机扫描测厚运动控制基本模型。通过基于静力平衡的测量位姿解算和基于首次回波能量... 详细信息

针对复杂曲面薄壁零件高效、精密在机测厚难题,提出一种面形自适应的超声在机测厚新方法,创新设计多功能高度集成的超声在机测厚装置,进一步建立超声在机扫描测厚运动控制基本模型。通过基于静力平衡的测量位姿解算和基于首次回波能量衰减的姿态偏角自动辨识,确定出传感器动态调整中的最佳测量姿态。对于具有固定时延的超声回波信号,利用所构造的步长控制函数,设计回波声时变步长自适应计算算法,可有效提高算法收敛速率和减小稳态误差。以弧形和S形薄壁件为典型对象,利用所研发的超声在机测厚系统,开展面形自适应超声在机测厚综合试验研究。试验表明,对在机测量的厚度数据实施姿态偏角误差补偿,其结果与三坐标测量机标定值相比较,测量精度可稳定在0.02 mm以内,满足了复杂薄壁零件在机测厚需求。

关键词：面形自适应超声在机测厚薄壁件姿态偏角声时计算

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基于权重复用的训练加速算法

实验技术与管理 2024年第5期41卷 15-22页

作者：应仰威章洛铭齐炜郑楷周泓浙江大学生物医学工程与仪器科学学院浙江杭州310027

深度学习已广泛应用在科研教学、工业生产等各领域,但因其数据量庞大和模型结构复杂,在模型训练阶段要依赖大量的计算资源。为了能在实验教学环节提升资源利用效率,让学生更加熟练地掌握数据搜集和模型参数调整优化的能力,提出了一种基... 详细信息

深度学习已广泛应用在科研教学、工业生产等各领域,但因其数据量庞大和模型结构复杂,在模型训练阶段要依赖大量的计算资源。为了能在实验教学环节提升资源利用效率,让学生更加熟练地掌握数据搜集和模型参数调整优化的能力,提出了一种基于权重复用的训练加速方法,分别对VGG和ResNet网络结构的深度和宽度进行伸缩拓展,允许模型复用结构相似但不需要完全一致的网络权重。实验结果表明,在CIFAR10数据集上测试,采用权重复用方法进行初始化的训练更快收敛,而且在训练结束时与随机化训练的准确率相近,实现拓展后的网络加速训练,是一种更加灵活的知识迁移方法,有助于培养学生对复杂模型的理解与优化能力。

关键词：卷积神经网络知识迁移训练加速权重复用

千瓦级微波等离子炬-原子发射光谱(MPT-AES)在油液分析中的应用

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高等学校化学学报 2018年第12期39卷 2651-2657页

作者：鄢雨微金伟朱旦张涛应仰威单锦张旭晨于丙文陈挺刘超金钦汉浙江大学控制科学与工程学院智能系统与控制研究所杭州310058 浙江全世科技有限公司杭州310053

采用千瓦级微波等离子炬-原子发射光谱(MPT-AES)装置对油液样品直接雾化进样分析,对直接稀释后的润滑油中8种金属元素进行了检测,并记录了进样时等离子体形貌的变化.结果表明,所有元素的校正曲线线性回归方程的R^2值均优于0. 995,精密度... 详细信息

采用千瓦级微波等离子炬-原子发射光谱(MPT-AES)装置对油液样品直接雾化进样分析,对直接稀释后的润滑油中8种金属元素进行了检测,并记录了进样时等离子体形貌的变化.结果表明,所有元素的校正曲线线性回归方程的R^2值均优于0. 995,精密度高,检出限接近传统的ICP-AES方法检出结果,为MPT-AES在油液视情维修中的分析监测及在线快速监测奠定了基础.同时还设计了一种油液在线混合进样装置,操作方便、进样量准确,适用于微量样品的采集和直接稀释及进样.

关键词：微波等离子炬润滑油元素检测进样装置

Seismic Recognition and Origin of Miocene Meishan Formation Contourite Deposits in the Southern Qiongdongnan Basin,Northern South China Sea

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Acta Geologica Sinica(English Edition) 2021年第1期95卷 131-141页

作者： FENG yangwei REN Yan LYU Chengfu ZHANG Peng CHEN ying JIN Li School of Geographical Science and Tourism Nanyang Normal UniversityNanyangHenan 473061China Shandong Key Laboratory of Depositional Mineralization&Sedimentary Mineral Shandong University of Science and TechnologyQingdaoShandong 266590China School of Earth Sciences East China University of TechnologyNanchang 330013China PetroJindian(Beijing)Sci-Tech Co. LtdBeijing 100000China Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000China CNOOC Research Institute Co. Ltd.Beijing 100028China

Research into the contourite deposits in the Upper Meishan Formation of the southern Qiongdongnan Basin in South China Sea is weak;their characteristics,distribution and original geological conditions are not *** geologic al and geophysical methods including seismic and drilling data,based on seismic reflection characteristics,geometrical configuration description,and wave impedance inversion,two types of contourite deposits are *** deposits have blurred boundaries between each deposit and disordered internal seismic reflections;They are mound-shaped only in transverse section,and banded in the longitudinal ***Ⅰcontourite deposits are conical,with mediumhigh amplitude,low-continuity,low-frequency mound-shaped seismic facies,and subparallel-chaotic reflections *** deposits are conical with sharp tops,the canal between mounds is V-shaped and *** western wing is gentle and the eastern wing is steep,with the slope toe mostly between 10°and 20°,and width height ratio about ***Ⅱcontourite deposits are flat,exhibiting medium-amplitude,medium-continuity,low-frequency mound-shaped seismic facies,with subparallel weak reflections *** mounds are flat with gently arced tops,with shallow canals *** slope toe is between 5°and 10°,with a width height ratio of about *** wave impedance value of these contourite deposits is 4.6 kg/m^(3)×m/s to 6.8 kg/m^(3)×m/s,about 5.8 kg/m^(3)×m/s on average,which is presumed to represent marlycalcareous clastic *** contourite deposits mainly develop beneath the slope break at the margin of the faultcontrolled platform in the Southern Uplift zone of the *** plane view,they are distributed approaching a west-to-east direction,and in section,lie in low-lying areas near the faults at fault-controlled terraces of the Southern Uplift zone,with a paleo-current direction nearly *** paleotectonic setting of the gentle monoclinic platform was fav

关键词： contourites seismic reflection characteristics Miocene Qiongdongnan basin South China

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超声在机测厚接触力控制方法研究

计算机测量与控制 2018年第11期26卷 47-51页

作者：刘海波应杨威廉盟周连杰王永青大连理工大学精密与特种加工教育部重点实验室辽宁大连116024

针对接触式超声在机自动测厚中可靠接触难题,提出了超声探头与被测工件之间接触力控制方法,制定了基于接触力实时反馈的闭环控制策略,建立法向接触力计算模型,设计了接触力调控量向机床位移校正量转化的阻抗模型与接触力滑模变结构控制... 详细信息

针对接触式超声在机自动测厚中可靠接触难题,提出了超声探头与被测工件之间接触力控制方法,制定了基于接触力实时反馈的闭环控制策略,建立法向接触力计算模型,设计了接触力调控量向机床位移校正量转化的阻抗模型与接触力滑模变结构控制器,在Simulink环境下对控制模型进行了数值仿真,验证了算法有效性,可实现超声在机测厚中恒定接触力精确跟踪控制;在所研制的测量系统中进行了测量实验,结果表明超声在机扫描测厚接触力控制误差在4N以内,实现了超声在机自动扫描测量过程中的接触状态保持,保证超声传感器输出信号稳定,测厚误差明显减小。

关键词：超声在机测厚接触力控制薄壁件

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基于持续跟踪调查的防御性驾驶行为分析模型

交通运输系统工程与信息 2020年第2期20卷 151-156页

作者：高红丽高丽英杨炜程范双双西南交通大学交通运输与物流学院成都611756 西华大学汽车与交通学院成都610039 汽车测控与安全四川省重点实验室成都610039 四川交通职业技术学院汽车工程系成都611130 成都纺织高等专科学校成都611731 四川(成都)两院院士咨询服务中心成都610041

为解决防御性驾驶行为心理作用过程缺少定量描述的问题,在界定防御性驾驶行为内涵的基础上,设计防御性驾驶行为量表.基于计划行为理论,构建以过去防御性驾驶行为、行为态度、主观规范和知觉行为控制为预测变量,行为意图为中介变量,后续... 详细信息

为解决防御性驾驶行为心理作用过程缺少定量描述的问题,在界定防御性驾驶行为内涵的基础上,设计防御性驾驶行为量表.基于计划行为理论,构建以过去防御性驾驶行为、行为态度、主观规范和知觉行为控制为预测变量,行为意图为中介变量,后续防御性驾驶行为为结果变量的分析模型.对非职业驾驶员在间隔3个月的两个时间点跟踪调查,第1次调查内容包括过去防御性驾驶行为、TPB变量、个人基本信息,第2次调查包括后续防御性驾驶行为和个人基本信息,获得两次调查数据完全匹配的有效问卷213份.对有效数据分析显示:主观规范对防御性驾驶行为意向不显著,知觉行为控制、行为态度和过去防御性驾驶行为对防御性驾驶行为意向影响值分别为0.40、0.29和0.26;行为态度、知觉行为控制和过去驾驶行为通过行为意向(0.36),可以在一定程度上对后续行为进行解释.

关键词：交通工程防御性驾驶行为计划行为理论非职业驾驶员跟踪调查

Surface evolution of Al-Si-Cu alloy in thermal shock under different heating speeds

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Journal of Central South University 2021年第10期28卷 2988-2998页

作者： LIU Lei ZHANG Hai-jun LI Bo-yan YANG Zhong BAO Tong LI Jian-ping GUO Yong-chun XIA Feng yangwei LI Hai-ying School of Materials and Chemical Engineering Xi'an Technological UniversityXi'an 710021China China North Engine Research Institute(Tianjin) Tianjin 300400China

In order to understand the initial surface damage of Al piston in unsteady thermal environment like knock combustion,T6 heat treated cast Al-Si-Cu alloy was thermal shocked under different heating speeds between room temperature and 450°C by adjusting the environmental *** surface evolution was mainly characterized in view of roughness,hardness,morphology,texture,phase and element *** indicated that both the roughness and hardness went up to the maximum and then decreased with rising heating ***-structure and phase analysis suggested that the interactions of solid phase transition and oxidation with enhancing thermal stress took responsible for the surface evolution.

关键词： Al alloy piston thermal shock heating speed surface roughness