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汽车转向机PCBA锡焊缺陷自动检测装置研究

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现代制造技术与装备 2024年第4期60卷 212-216页

作者：谢非王宗荣李楠南京工程学院机械工程学院南京211167 儒拉玛特自动化技术(苏州)有限公司苏州215021

为了提高汽车转向机自动化装配生产线焊接检测的效率,将缺陷自动检测技术应用于汽车转向机印制电路板(Printed Circuit Board Assembly,PCBA)自动锡焊生产,研发出汽车转向机的自动锡焊检测装置。一方面对控制器、电缸、相机等硬件设备... 详细信息

为了提高汽车转向机自动化装配生产线焊接检测的效率,将缺陷自动检测技术应用于汽车转向机印制电路板(Printed Circuit Board Assembly,PCBA)自动锡焊生产,研发出汽车转向机的自动锡焊检测装置。一方面对控制器、电缸、相机等硬件设备进行选型和设计,另一方面进行锡焊焊点的图像识别、特征提取等算法的设计。在现场对多组次产品进行拍照,对采集的焊点图像进行大量试验。结果显示,该装置准确率为98.2%,误检率为1.2%,漏检率为0.6%,每张图像平均检测时间为122.47ms,达到工程的质量要求,有效提高了PCBA锡焊缺陷的检测效率和可靠性。

关键词：印制电路板(PCBA) 汽车转向机锡焊缺陷自动检测图像识别特征提取

Steady-State Creep Behavior of Super304H Austenitic Steel at Elevated Temperatures

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Acta Metallurgica Sinica(English Letters) 2015年第11期28卷 1336-1343页

作者： Ping Ou Long Li Xing-fei xie Jian Sun Shanghai Key Laboratory of Advanced High-Temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiaotong University School of Materials Science and Engineering Jiangxi University of Science and Technology

Creep behavior of Super304H austenitic steel has been investigated at elevated temperatures of 923-973 K and at applied stress of 190-210 MPa. The results show that the apparent stress exponent and activation energy in the creep deformation range from 16.2 to 27.4 and from 602.1 to 769.3 kJ/mol at different temperatures, respectively. These high values imply the presence of a threshold stress due to an interaction between the dislocations and Cu-rich precipitates during creep deformation. The creep mechanism is associated with the dislocation climbing governed by the matrix lattice diffusion. The origin of the threshold stress is mainly attributed to the coherency strain induced in the matrix by Cu-rich precipitates. The theoretically estimated threshold stresses from Cu-rich precipitates agree reasonably with the experi- mental results.

关键词： Super304H steel Cu-rich precipitate Creep Threshold stress

Single Peak Solutions for a Schr?dinger Equation with Variable Exponent

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Acta Mathematica Sinica,English Series 2023年第11期39卷 2207-2218页

作者： Zhong Yuan LIU Peng LUO Hua fei xie School of Mathematics and Statistics He’nan UniversityKaifeng 475004P.R.China School of Mathematics and Statistics&Hubei Key Laboratory of Mathematical Sciences Central China Normal UniversityWuhan 430079P.R.China School of Mathematics and Statistics Nanyang Normal UniversityNanyang 473061P.R.China

We study the following Schr?dinger equation with variable exponent−Δu+u=u^(p+∈a)(x),u>0 in R^(N),where∈>0,1 详细信息

We study the following Schr?dinger equation with variable exponent−Δu+u=u^(p+∈a)(x),u>0 in R^(N),where∈>0,1

关键词： Single peak solutions Schr?dinger equation variable exponent

Increasing Surface UV Radiation in the Tropics and Northern Mid-Latitudes due to Ozone Depletion after 2010

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Advances in Atmospheric Sciences 2023年第10期40卷 1833-1843页

作者： fei xie Yan XIA Wuhu FENG Yingli NIU School of Systems Science and College of Global Change and Earth System Science Beijing Normal UniversityBeijing 100875China National Centre for Atmospheric Science University of LeedsLeeds LS29PHUK Istitute for Climate and Atmospheric Science School of Earth and EnvironmentUniversity of LeedsLeeds LS29JTUK

Excessive exposure to ultraviolet(UV)radiation harms humans and *** level of surface UV radiation had increased due to declines in stratospheric ozone in the late 1970s in response to emissions of *** the implementation of the Montreal Protocol,the stratospheric loading of chlorine/bromine peaked in the late 1990s and then decreased;subsequently,stratospheric ozone and surface UV radiation would be expected to recover and decrease,***,we show,based on multiple data sources,that the May–September surface UV radiation in the tropics and Northern Hemisphere mid-latitudes has undergone a statistically significant increasing trend[about 60.0 J m^(–2)(10 yr)^(–1)]at the 2σlevel for the period 2010–20,due to the onset of total column ozone(TCO)depletion[about−3.5 DU(10 yr)^(–1)].Further analysis shows that the declines in stratospheric ozone after 2010 could be related to an increase in stratospheric nitrogen oxides due to increasing emissions of the source gas nitrous oxide(N_(2)O).

关键词： surface UV radiation stratospheric ozone stratospheric chemistry N_(2)O

Research on the dynamic characteristics of pneumatic proportional regulator in pneumatic-loading system and design of fuzzy adaptive controller

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Science China(Technological Sciences) 2022年第4期65卷 956-965页

作者： WANG Na XU LuYu xie fei SHI Yan WANG YiXuan Engineering Training Center Beihang UniversityBeijing 100191China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Department of Pulmonary and Critical Care Medicine Chinese PLA General HospitalBeijing 100191China

Pneumatic proportional control servo regulator is the core component of a pneumatic-loading experimental system,which is very important in solving the overcharging ***,previous research on control of pneumatic proportional regulator in a pneumatic-loading experimental system led to failure in analysis of the influence of opening error of the switch regulator because it did not analyze the regulator basic working principle and *** traditional control method cannot fully solve the overcharging problem nor ensure adequate control performance of the *** seriously studying the working principle and key mechanical parameters of the valve,a fuzzy parameter-adaptive controller is designed by introducing a linear mixture of the pressure and opening errors of the switch regulator to reduce pressure overshoot and optimize its control *** to the fuzzy-control strategy based on the working characteristics and mechanical parameters of the valve,the overshoot phenomenon of the pneumatic-loading system is solved,and the pressure overshoot is *** error of the output air pressure of the regulator is 1.24%,which is *** adjustable pressure range of the regulator is 0.2–0.6 *** maximum deviation is 0.012 *** linearity of the case is 1.34%F.S.

关键词： pneumatic proportional servo regulator pneumatic-loading experimental system mathematical model fuzzy parameter-adaptive controller opening error of the switch regulator

分化抑制因子家族在慢性髓系白血病中的表达及临床意义

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中国肿瘤临床 2024年第14期51卷 710-715页

作者：周静东解飞袁倩郭竑林江张婷娟钱军江苏大学附属人民医院血液科镇江市血液病临床医学研究中心镇江市血液系统恶性肿瘤精准诊断与治疗重点实验室

目的：探索分化抑制因子（inhibitor of differentiation,ID）家族在慢性髓系白血病（chronic myeloid leukemia,CML）中的表达和启动子甲基化水平，并分析其临床意义。方法：应用定量PCR及定量甲基化特异性PCR的方法检测2010年1月至201... 详细信息

目的：探索分化抑制因子（inhibitor of differentiation,ID）家族在慢性髓系白血病（chronic myeloid leukemia,CML）中的表达和启动子甲基化水平，并分析其临床意义。方法：应用定量PCR及定量甲基化特异性PCR的方法检测2010年1月至2017年12月期间江苏大学附属人民医院就诊的非恶性血液病患者（对照组）和CML患者骨髓单个核细胞中ID2/ID3/ID4表达及ID4启动子甲基化水平，通过分组分析ID家族异常的临床意义。结果：ID2及ID3表达在CML患者中均呈现显著上调（P<0.001,P<0.05），而ID4表达在CML患者中呈现显著下调（P<0.01）。其中，接受者操作特征曲线分析揭示ID2表达可作为CML鉴别的潜在分子标志物（AUC=0.895,P<0.001）。CML患者中ID4启动子高甲基化概率显著高于对照组患者（P=0.001），且ID4启动子甲基化与ID4表达呈现负相关（r=-0.424,P=0.002）。通过分组分析发现ID2高表达较易发生于男性患者中（P=0.040）;ID4低表达/高甲基化较易发生于加速/急变期患者（P=0.003,P<0.001）。此外，CML加速/急变期患者ID4表达水平低于慢性期患者（P<0.001），而ID4甲基化水平高于慢性期患者（P<0.001）。通过单因素及多因素Logistic回归分析发现ID4高甲基化是CML患者疾病进展的独立危险因素（P=0.007）。结论：ID家族在CML患者中表达态势不同，其中ID2/ID3表达上调；而ID4表达下调，与ID4启动子高甲基化相关。ID4表达/甲基化与CML疾病进展相关，其中ID4甲基化可能是CML疾病进展的独立危险因素。

关键词：慢性髓系白血病分化抑制因子表达甲基化临床意义

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某金属氧化物储存容器设计及储存工况优化

机械设计 2024年第S1期41卷 177-182页

作者：张朋吴德慧马敬周冠辰谢非苑斯雯中国核电工程有限公司北京100840

某金属氧化物是一种具有高放射性的核工业后处理产物,其在密封储存过程中释放热量并产生氢气和氦气,导致储存容器温度升高、内部压力增大。为了确保某金属氧化物长周期储存安全性,文中深入分析其储存特性演变规律及储存工况参数,设计储... 详细信息

某金属氧化物是一种具有高放射性的核工业后处理产物,其在密封储存过程中释放热量并产生氢气和氦气,导致储存容器温度升高、内部压力增大。为了确保某金属氧化物长周期储存安全性,文中深入分析其储存特性演变规律及储存工况参数,设计储存容器采用数值模拟探究储存工况对容器温度、压力的影响,进而验证储存容器结构合理性并优化储存工况。结果表明:提高冷却风速、降低冷却风温、增大堆积密度及适量的含水率有利于金属氧化物在储存过程中传热冷却,其中冷却风速对该金属氧化物温度影响最大;降低含水率、提高冷却风速、增大堆积密度及降低冷却风温有利于避免储存过程中内压过高,其中金属氧化物含水率的升高对容器压力的增加影响显著,在实际储存中需要严格控制金属氧化物中的水分含量。

关键词：储存时间堆密度金属氧化物含水率数值模拟

Conceptual design and safety characteristics of a new multi-mission high flux research reactor

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Nuclear Science and Techniques 2023年第3期34卷 9-24页

作者： Wei Xu Jian Li Heng xie Zhi-Hong Liu Jing Zhao fei xie Lei Shi School of Nuclear Science and Engineering Beijing Key Laboratory of Passive Safety Technology for Nuclear EnergyNorth China Electric Power UniversityBeijing 102206China Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy TechnologyKey Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China

Research reactors with neutron fluxes higher than 10^(14) n cm^(−2) s^(−1) are widely used in nuclear fuel and material irradiation,neutron-based scientific research,and medical and industrial isotope *** high flux research reactors are not only important scientific research facilities for the development of nuclear energy but also represent the national comprehensive technical *** has several high flux research reactors that do not satisfy the requirements of nuclear energy development.A high flux research reactor has the following features:a compact core arrangement,high power density,plate-type fuel elements,a short refueling cycle,and high coolant velocity in the *** characteristics make it difficult to simultaneously realize high neutron flux and optimal safety margin.A new multi-mission high flux research reactor was designed by the Institute of Nuclear and New Energy Technology at Tsinghua University in China;the reactor can simul-taneously realize an average neutron flux higher than 2.0×10^(15) n cm^(−2) s^(−1) and fulfill the current safety *** high flux research reactor features advanced design concepts and has sufficient safety margins according to the preliminary safety *** on the analysis of the station blackout accident,loss of coolant accident,and reactivity accident of a single-control drum rotating out accidently,the maximum temperature of the cladding surface,minimum departure from nucleate boiling ratio,and temperature difference to the onset of nucleate boiling temperature satisfy the design limits.

关键词： High flux research reactor Neutron flux Safety analysis Maximum temperature of cladding surface Departure from nucleate boiling ratio

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急倾斜煤层采空区输气管道变形模拟

科学技术与工程 2024年第17期24卷 7082-7089页

作者：杜凤李瑞盛宇任帅孙东旭吴明谢飞内蒙古西部天然气股份有限公司生产技术部鄂尔多斯017000 辽宁石油化工大学石油天然气工程学院抚顺113001

为了探究急倾斜煤层开采形成的采空区对其上覆输气管道安全运行的影响,基于快速拉格朗日法对某煤层采空区进行数值模拟,探究了实际煤矿采空区的地质沉降和管道位移特征,研究了不同倾角、不同开采深度的急倾斜煤层对上覆输气管道变形的... 详细信息

为了探究急倾斜煤层开采形成的采空区对其上覆输气管道安全运行的影响,基于快速拉格朗日法对某煤层采空区进行数值模拟,探究了实际煤矿采空区的地质沉降和管道位移特征,研究了不同倾角、不同开采深度的急倾斜煤层对上覆输气管道变形的影响。结果表明:煤矿区5个急倾斜煤层在开采100 m后,在煤层坡面上方形成最大深度1.54 m的塌陷,塌陷区内的土壤和岩石主要向煤层方向水平移动和垂直向下移动;靠近煤层采空区的管道,垂直方向位移大于水平方向位移,而远离煤层采空区管道,则水平位移较大;随着急倾斜煤层倾角减小和开采深度增大,管道向下的沉降量增大,并且发生最大沉降的位置逐渐向煤层方向靠近。

关键词：急倾斜煤层输气管道采空区塌陷数值模拟