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基于改进麻雀搜索算法优化BPNN的电阻点焊质量预测

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天津大学学报（自然科学与工程技术版） 2024年第5期57卷 445-451页

作者：罗震董建伟胡建明天津大学材料科学与工程学院天津300350

电阻点焊技术由于具有高效、自动化程度高等焊接特点,被广泛应用于汽车、航空航天和公共交通等制造领域,由于焊点在封闭状态下进行,焊接过程存在诸多影响因素且无法直接检测,因此,准确预测电阻点焊质量是生产过程中必不可少的环节.本文... 详细信息

电阻点焊技术由于具有高效、自动化程度高等焊接特点,被广泛应用于汽车、航空航天和公共交通等制造领域,由于焊点在封闭状态下进行,焊接过程存在诸多影响因素且无法直接检测,因此,准确预测电阻点焊质量是生产过程中必不可少的环节.本文以2219/5A06铝合金为研究对象,在3种不同的装配条件(包括间隙和间距)下进行电阻点焊工艺信号的分析,并进行人工智能建模.为了提高电阻点焊质量评价的性能和效率,本文采用Logistic-Tent(LT)复合映射改进麻雀搜索算法(SSA)对反向传播神经网络(LT-SSA-BPNN)模型进行优化,模型的输入和输出分别为多信号融合后的变量和熔核直径.实验结果表明,与传统的标准反向传播神经网络(BPNN)模型相比,经过LT-SSA-BP模型优化后,预测结果的平均绝对误差(MAE)、均方误差(MSE)和均方根误差(RMSE)分别降低了36.17%、17.55%和51.75%.同时,LT-SSA-BP神经网络在添加了不同间隙和间距条件作为训练集后,其预测稳定性明显提高,可以成功预测电阻点焊质量.

关键词：电阻点焊质量预测麻雀搜索算法反向传播神经网络模型

Farnesyltransferase inhibitor lonafarnib suppresses respiratory syncytial virus infection by blocking conformational change of fusion glycoprotein

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2970-2983页

作者： Qi Yang Bao Xue Fengjiang Liu Yongzhi Lu Jielin Tang Mengrong Yan Qiong Wu Ruyi Chen Anqi Zhou Lijie Liu Junjun Liu Changbin Qu Qingxin Wu Muqing Fu Jiayi Zhong jianwei dong Sijie Chen Fan Wang Yuan Zhou Jie Zheng Wei Peng Jinsai Shang Xinwen Chen Guangzhou National Laboratory Guangzhou 510005China State Key Laboratory of Respiratory Disease Guangzhou Medical UniversityGuangzhou 511436China Wuhan Institute of Virology Chinese Academy of SciencesWuhan 430071China School of Basic Medical Sciences Guangzhou Medical UniversityGuangzhou 511436China GMUGIBH Joint School of Life Sciences Guangzhou Medical UniversityGuangzhou 511436China Guangzhou Institutes of Biomedicine and Health Chinese Academy of SciencesGuangzhou 510530China Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai 201203China School of Pharmaceutical Science and Technology Hangzhou lnstitute for Advanced StudyUCASHangzhou 310024China

Respiratory syncytial virus(RSV)is the major cause of bronchiolitis and pneumonia in young children and the *** are currently no approved RSV-specific therapeutic small molecules *** high-throughput antiviral screening,we identified an oral drug,the prenylation inhibitor lonafarnib,which showed potent inhibition of the RSV fusion *** exhibited antiviral activity against both the RSV A and B genotypes and showed low cytotoxicity in HEp-2 and human primary bronchial epithelial cells(HBEC).Time-of-addition and pseudovirus assays demonstrated that lonafarnib inhibits RSV entry,but has farnesyltransferase-independent antiviral ***-electron microscopy revealed that lonafarnib binds to a triple-symmetric pocket within the central cavity of the RSV F metastable pre-fusion *** at the RSV F sites interacting with lonafarnib showed resistance to lonafarnib but remained fully sensitive to the neutralizing monoclonal antibody ***,lonafarnib dose-dependently reduced the replication of RSV in BALB/c ***,lonafarnib could be a potential fusion inhibitor for RSV infection.

关键词： neutral metastable approved

高频感应熔覆NiTiFe合金涂层摩擦学性能研究

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润滑与密封 2024年第2期49卷 11-18页

作者：董建伟郭岩宝王德国张政中国石油大学(北京)机械与储运工程学院北京102249

为增强金属材料表面的耐磨性能,采用高频感应熔覆技术,在HT300基底表面制备出NiTiFe合金涂层;利用扫描电子显微镜(SEM)、能谱仪(EDS)、显微硬度计和X射线衍射仪(XRD)对NiTiFe合金涂层的微观组织、元素组成、硬度、相组成和与基底的结合... 详细信息

为增强金属材料表面的耐磨性能,采用高频感应熔覆技术,在HT300基底表面制备出NiTiFe合金涂层;利用扫描电子显微镜(SEM)、能谱仪(EDS)、显微硬度计和X射线衍射仪(XRD)对NiTiFe合金涂层的微观组织、元素组成、硬度、相组成和与基底的结合情况进行表征与分析;通过摩擦磨损试验机对涂层的摩擦学性能进行测试,对其摩擦磨损机制进行分析。结果表明:涂层组织致密,无裂缝和空隙,成型质量良好,平均厚度达到0.7 mm,与HT300基底实现了冶金结合;涂层中主要包含Fe2Ti、Fe6.94Ti0.36和Ni3Fe三种相,Fe元素的加入使涂层的晶格发生畸变,硬度提高,平均硬度达到997.36HV,约为HT300基底平均硬度值的5倍。通过摩擦磨损试验发现,试验前期,NiTiFe合金涂层与对摩副之间的摩擦因数较低,维持在0.2左右,对摩副的失效导致摩擦副之间的接触形式发生改变,摩擦因数产生阶跃;随着载荷的增加,涂层上呈现的磨痕宽度在不断增加,对摩副由于磨损造成的材料去除后暴露出的面积也在不断增大。摩擦磨损试验后,NiTiFe合金涂层摩擦表面光滑平整,仅出现了轻微的磨粒磨损,磨损体积远小于对摩副,表现出优良的耐摩擦磨损性能。

关键词：高频感应熔覆 NiTi合金界面反应硬度摩擦学性能

Existence of Classical Solutions to a Stationary Simplified Quantum Energy-Transport Model in 1-Dimensional Space

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Chinese Annals of Mathematics,Series B 2013年第5期34卷 691-696页

作者： jianwei dong Youlin ZHANG Shaohua CHENG Department of Mathematics and Physics Zhengzhou Institute of Aeronautical Industry Management Library Zhengzhou Institute of Aeronautical Industry Management

The existence of classical solutions to a stationary simplified quantum energytransport model for semiconductor devices in 1-dimensional space is *** model consists of a nonlinear elliptic third-order equation for the electron density,including a temperature derivative,an elliptic nonlinear heat equation for the electron temperature,and the Poisson equation for the electric *** proof is based on an exponential variable transformation and the Leray-Schauder fixed-point theorem.

关键词： Quantum energy-transport model Stationary solutions Existence

SOME SPECIAL SELF-SIMILAR SOLUTIONS FOR A MODEL OF INVISCID LIQUID-GAS TWO-PHASE FLOW

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Acta Mathematica Scientia 2021年第1期41卷 114-126页

作者： jianwei dong Manwai YUEN School of Mathematics Zhengzhou University of AeronauticsZhengzhou 450015China Department of Mathematics and Information Technology The Education University of Hong Kong10 Lo Ping RoadTai PoNew TerritoriesHong KongChina

In this article,we are concerned with analytical solutions for a model of inviscid liquid-gas two-phase *** the basis of Yuen’s works[25,27–29]on self-similar solutions for compressible Euler equations,we present some special self-similar solutions for a model of inviscid liquid-gas two-phase flow in radial symmetry with and without rotation,and in elliptic symmetry without *** blowup phenomena and the global existence of the solutions obtained are classified.

关键词： two-phase flow analytical solutions self-similar blowup global solutions

Application of Hydrocracking Process for Upgrading Tail Oil Quality in 1.0 Mt/a Hydrocracker Unit at SINOPEC Yangzi Petrochemical Company

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China Petroleum Processing & Petrochemical Technology 2009年第1期11卷 13-17页

作者： Zhang Haichun dong jianwei SINOPEC Yangzi Petrochemical Company Nanjing 210048 SINOPEC Research Institute of Petroleum Processing

This article focuses on the hydrocracking technology for upgrading the quality of tail oil and the first commercial application of the RN-32V/RHC- 1 catalysts in the 1.0 Mt/a hydrocracker at the Yangzi Petrochemical Company, which was started up successfully in September 2008. One month after start-up of the hydrocracking unit, an evaluation opera- tion has been conducted fbr assessing the catalysts performance. The technical calibration results showed that the RN- 32V/RHC-1 catalysts had high activity, and the product yield distribution was reasonable. The hydrocracker can provide abundant feedstocks for the downstream aromatic production unit and ethylene production unit.

关键词： hydrocracking upgrading tail oil quality catalysts application

Multisource Target Classification Based on Underwater Channel Cepstral Features

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Journal of Ocean University of China 2022年第4期21卷 917-925页

作者： LI Xiukun JIA Hongjian dong jianwei QIN Jixing College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001China Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001China State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of SciencesBeijing 100190China

Passive target detection through shipping-radiated noise is a key technology in current underwater operations and is of great research value in civil and military *** this study,the stable spectral line component of shipping-radiated noise is used as the research object,and the classification of multisource targets is studied from the perspective of underwater *** utilize the channel impulse response function as the classification basis of different ***,the underwater channel is estimated by the ***,the channel cepstral features carried by different spectral line components are extracted in ***,the spectral line components belonging to the same target are clustered by the cepstral feature distance to realize the classification of different *** simulation and experimental results verify the effectiveness of the proposed method in this research.

关键词： shipping-radiated noise underwater channel cepstral features target classification

潮汕海岸带红树林小型底栖动物的群落特征及生态环境质量评价

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海洋学报 2024年第5期46卷 68-80页

作者：范魏丰唐荣叶俞越王洋耿乐董建玮杜永芬南京师范大学海洋科学与工程学院江苏南京210023 中国科学院海洋研究所海洋生物分类与系统演化实验室青岛市海洋生物多样性与保护重点实验室山东青岛266071 中国地质调查局海口海洋地质调查中心海南海口571127

红树林是海岸带的重要生态屏障,也是气候变化和人类活动的敏感区;底栖动物是对环境变化最直接的响应群体。基于2021年4月在潮汕海岸带红树林分布区7个站位的现场观测和样品采集,对沉积物环境、小型底栖动物的群落特征、空间分布及生态... 详细信息

红树林是海岸带的重要生态屏障,也是气候变化和人类活动的敏感区;底栖动物是对环境变化最直接的响应群体。基于2021年4月在潮汕海岸带红树林分布区7个站位的现场观测和样品采集,对沉积物环境、小型底栖动物的群落特征、空间分布及生态环境质量进行了分析。研究区共发现15个小型底栖动物类群,自由生活海洋线虫占丰度上的绝对优势(90.32%);多毛类在生物量上居首(58.44%)。小型底栖动物平均丰度较其他红树林略高,其丰度分布和海洋线虫丰度,叶绿素a、脱镁叶绿酸、有机碳和重金属(Cd、Zn、Cu、Cr和Hg)含量具有相似的空间格局:中部区域莲阳河北岸最高,向南向北均降低。不同斑块间的动物群落相似性较高(70%),解释其群落结构差异分布的最佳环境因子是重金属Pb。海洋线虫与桡足类的丰度比(N/C)、潜在生态风险指数和沉积物质量分级结果均表明研究区环境质量整体较差。

关键词：红树林小型底栖动物重金属污染生态评价潮汕海岸带

Variations in concentrations and bioavailability of heavy metals in rivers caused by water conservancy projects： Insights from water regulation of the Xiaolangdi Reservoir in the Yellow River

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Journal of Environmental Sciences 2018年第12期30卷 79-87页

作者： jianwei dong Xinghui Xia Zhining Zhang Zixuan Liu Xiaotian Zhang Husheng Li State Key Laboratory of Water Environment Simulation Key Laboratory for Water and Sediment Sciences of Ministry of EducationSchool of Environment Beijing Normal University Beijing 100875 China Center for Eco-Environmental Research Nanjing Hydraulic Research Institute Nanjing 210029 China Beijing Center for Physical & Chemical Analysis Beijing 100089 China Hubei Provincial Center for Disease Control and Prevention Wuhan 430079 China

Water regulation of the Xiaolangdi Reservoir of the Yellow River was chosen as a case to investigate variations in concentrations and bioavailability of heavy metals caused by water conservancy projects in rivers. Water and suspended sediment（SPS） samples were collected at downstream sampling sites along the river during this period. Concentrations and speciation of Zn, Cr, Cu, Ni, and Pb in water and SPS samples were analyzed, and their bioaccumulation was studied with Daphnia magna. This study indicated that the exchangeable and carbonatebound fractions of heavy metals in SPS decreased along the studied stretch, and the dissolved heavy metal concentrations increased along the river with 1.6–15 folds. This is because sediment resuspension increased along the river during water regulation, giving rise to the increase of heavy metal release from SPS. The dissolved Zn, Cu, Ni, and Pb concentrations were significantly positively correlated with SPS concentrations, and their increase along the river was greater than Cr. The body burdens of heavy metals in D. magna exposed into samples collected from the reservoir outlet were 1.3–3.0 times lower than those from downstream stations, suggesting that the heavy metal bioavailability increased during water *** should be considered in the reservoir operation.

关键词： Heavy metals Speciation Bioaccumulation Suspended sediment Dam Water conservancy project