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基于机器学习的沥青路面压实度质量评估

济南大学学报（自然科学版） 2024年第3期38卷 331-340页

作者：赵琪张健张智民陈镇文刘泽佳周立成刘逸平华南理工大学土木与交通学院广东广州510641 广州城投路桥工程有限公司广东广州510199

为了提高沥青路面压实度预测的准确率,基于机器学习对沥青路面进行压实度质量评估;通过对比实际工程中不同压路机在沥青路面上的振动规律,构建振动压路机-沥青路面系统动力学模型,利用Simulink数值仿真软件对所构建的模型进行仿真,设计... 详细信息

为了提高沥青路面压实度预测的准确率,基于机器学习对沥青路面进行压实度质量评估;通过对比实际工程中不同压路机在沥青路面上的振动规律,构建振动压路机-沥青路面系统动力学模型,利用Simulink数值仿真软件对所构建的模型进行仿真,设计8种工况,对比压实度计值、压实度控制值、机械驱动功率、滚轮综合刚度、填筑体能量、单位体积压实功率6个压实度质量评估指标在各工况下的适用性差异;采用支持向量机、逻辑回归、k最近邻、决策树、朴素贝叶斯法5种传统的机器学习方法对各工况下的压实度质量评估指标样本进行训练,对比压实度预测准确率;设计压路机在不同碾压次数时的碾压路线,对比分别采用最优压实度质量评估指标和单一压实度质量评估指标的压实度预测准确率。结果表明:不同压实度质量评估指标在不同工况下的适用性不同,即使在同一种工况下,不同碾压次数时的适用性也存在差异;采用最优压实度质量评估指标代替单一压实度质量评估指标,压实度预测准确率提高5.8%;在5种传统的机器学习方法中,朴素贝叶斯法预测最优压实度质量评估指标类型的准确率最高,为96.22%。

关键词：沥青路面压实度质量评估机器学习压实度动力学模型

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基于桥梁响应统计信息的智能损伤识别方法

合肥工业大学学报（自然科学版） 2019年第12期42卷 1667-1671页

作者：蒋雍建刘逸平周立成刘泽佳程楠汤立群华南理工大学土木与交通学院广东广州510641 华南理工大学亚热带建筑科学国家重点实验室广东广州510641

文章以珠江黄埔大桥北汊斜拉桥为研究对象,采用有限元模型计算了桥梁在随机车流作用下不同拉索损伤工况所对应的应变响应,进一步采用应变响应统计信息,引入随机森林和梯度提升决策树2种机器学习算法对损伤拉索进行识别,从而提出了一种... 详细信息

文章以珠江黄埔大桥北汊斜拉桥为研究对象,采用有限元模型计算了桥梁在随机车流作用下不同拉索损伤工况所对应的应变响应,进一步采用应变响应统计信息,引入随机森林和梯度提升决策树2种机器学习算法对损伤拉索进行识别,从而提出了一种结合桥梁响应统计信息与机器学习的损伤识别方法。计算结果表明,该方法在损伤定位和定量上均表现出良好的效果,验证了其应用于大跨度桥梁的可行性和有效性。该文提出的方法为有效利用桥梁长期健康监测数据进行损伤识别提供了思路。

关键词：桥梁健康监测有限元损伤识别统计特征机器学习

基于移动时间窗和时空窗主成分分析组合特征的损伤识别方法

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实验力学 2023年第1期38卷 17-27页

作者：魏能周立成张舸刘泽佳刘逸平蒋震宇杨宝汤立群华南理工大学土木与交通学院广东广州510641 华南理工大学亚热带建筑科学国家重点实验室广东广州510641 广东省建筑工程集团有限公司建筑科学研究院广东广州510000

近年来,机器学习算法在结构损伤识别领域得到了广泛应用。已有研究表明,设计良好的输入特征能够适应多种算法,从而减少调参时间和计算成本,并提高算法的识别准确率。本文引入移动主成分分析和时空窗主成分分析方法提取损伤敏感的特征组... 详细信息

近年来,机器学习算法在结构损伤识别领域得到了广泛应用。已有研究表明,设计良好的输入特征能够适应多种算法,从而减少调参时间和计算成本,并提高算法的识别准确率。本文引入移动主成分分析和时空窗主成分分析方法提取损伤敏感的特征组合作为机器学习输入,使用双跨平面梁有限元模型生成的模拟应变数据对组合特征的损伤识别效果进行验证。结果表明,良好的特征向量组合对损伤更加敏感,不仅有助于识别在传感器周围发生的损伤,而且能有效地定位结构边缘和远离传感器位置处的损伤,从而提高算法的损伤识别效果。此外,多种噪声强度下的实验表明,组合特征具有良好的鲁棒性,能较好地适应外界环境的变化。

关键词：移动主成分分析时空窗主成分分析组合特征机器学习损伤识别

Hexagonal FeNi2Se4@C Nanoflakes as High Performance Anode Materials for Sodium-ion Batteries

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Chemical Research in Chinese Universities 2021年第2期37卷 318-322页

作者： MA Cui QIU licheng BAO Jian zhou Yongning Department of Materials Science Fudan UniversityShanghai200433P.R.China

Metal selenides have drawn significant attention as promising anode materials for sodium-ion batteries(SIBs)owing to their high electronic conductivity and reversible ***,hexagonal FeNi2Se4@C nanoflakes were synthesized via a facile one-step hydrothermal *** deliver a reversible capacity of 480.7 mA·h/g at 500 mA/g and a high initial Coulombic efficiency of 87.8%.Furthermore,a discharge capacity of 444.8 mA·h/g can be achieved at 1000 mA/g after 180 *** sodium storage mechanism of FeNi2Se4@C is *** the discharge process,Fe and Ni nanoparticles are generated and distributed in Na2Se matrix *** the charge process,FeNi2Se4 phase is formed *** reversible phase conversion of FeNi2Se4@C during cycling is responsible for the excellent electrochemical performance and enables FeNi2Se4@C nanoflakes promising anode materials for SIBs.

关键词： Sodium-ion battery Metal selenide Anode Sodium storage

Gas production analysis for the buffer layer of high-voltage cross-linked polyethylene cables

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High Voltage 2024年第5期9卷 1149-1158页

作者： Wenqing zhou licheng Li Hao Cheng Xun Wu Gang Liu School of Electric Power Engineering South China University of Technology GuangzhouChina 2Analytical and Testing CenterSouth China University of Technology GuangzhouChina 3Dongguan Power Supply Bureau of Guangdong Power Grid Co.Ltd.DongguanChina

The cross-linked polyethylene insulated cables with corrugated aluminium-sheathed are widely used in urban power ***,a new type of power cable fault has emerged,primarily due to defects in the buffer ***,there is a notable lack of effective evaluation methods for these defects in high-voltage(HV)***,a theoretical analysis of the gas generation mechanism in the cable buffer layer was conducted,identifying distinct gas products at different ***,the diffusion kinetics of gas within the cable was studied,highlighting the importance of gas in determining the state of the buffer *** authors then collected and analysed 60 sets of buffer layer gases from two operational 110 kV HV cables using gas chromatography *** these results with the findings from on-site inspections,the characteristic gas components and concentration distribution under various defect conditions were *** results found higher concentrations of CH_(4)in normal cables and defective cables,while there are higher concentrations of H_(2),CO and CO_(2)in defective cables,and the oxygen content *** discoveries made in this research may offer a new approach for assessing the state of the cable buffer layer.

关键词： layer analysis cross

不同水质评价方法在浏阳河水质评价中的应用比较

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绿色科技 2020年第2期22卷 106-108页

作者：彭小玉周理程毕军平甘杰梁菁湖南省生态环境监测中心湖南长沙410019 国家环境保护重金属污染监测重点实验室湖南长沙410019 湖南省环境保护科学研究院湖南长沙410004

以浏阳河8个常规监测断面2016年监测水质数据为基础,运用单因子评价法、水污染指数法、综合水质标识指数法、综合污染指数法和内梅罗指数法5种评价方法对其水质进行了综合评价。结果表明:水污染指数法在浏阳河水质评价中具有较好的适用... 详细信息

以浏阳河8个常规监测断面2016年监测水质数据为基础,运用单因子评价法、水污染指数法、综合水质标识指数法、综合污染指数法和内梅罗指数法5种评价方法对其水质进行了综合评价。结果表明:水污染指数法在浏阳河水质评价中具有较好的适用性,单因子评价法无法进行水质定量评价,综合污染指数法和内梅罗指数法无法进行水质类别的评价,综合水质标识指数法评价结果过于乐观。

关键词：单因子评价法水污染指数法综合水质标识指数法综合污染指数法内梅罗指数法水质评价

二氧化硅薄膜中微纳球型结构对可见光吸收性能影响

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粘接 2022年第8期49卷 102-106页

作者：张桐刘孝丽钟浩周利成张涵榆林学院陕西榆林719000

设计在单一玻璃结构中加入具有周期性空气球形微纳结构,从而逐层改变空气的折射率,达到类似传统的多层的抗反射薄膜性能,或者更优。运用FDTD软件对二氧化硅薄膜展开仿真模拟,探究二氧化硅薄膜中的微纳球型结构对可见光吸收性能的影响,利... 详细信息

设计在单一玻璃结构中加入具有周期性空气球形微纳结构,从而逐层改变空气的折射率,达到类似传统的多层的抗反射薄膜性能,或者更优。运用FDTD软件对二氧化硅薄膜展开仿真模拟,探究二氧化硅薄膜中的微纳球型结构对可见光吸收性能的影响,利用FDTD软件模拟了微纳球形的结构尺寸、占空比、分布周期对二氧化硅微纳球形薄膜抗反射性能的影响规律,还模拟了不同颜色光照下对应微纳球型结构的反射率。最后得到抗反射效果最好的二氧化硅微纳球型结构的相关参数。

关键词：太阳能二氧化硅增透膜微纳球型结构

The 2020–2021 prolonged La Niña evolution in the tropical Pacific

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Science China Earth Sciences 2022年第12期65卷 2248-2266页

作者： Chuan GAO Maonan CHEN Lu zhou licheng FENG Rong-Hua ZHANG Key Laboratory of Ocean Circulation and Waves Institute of OceanologyCenter for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China Laoshan Laboratory Qingdao 266237China School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 210044China University of Chinese Academy of Sciences Beijing 100029China Center for Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an 710061China National Marine Environmental Forecasting Center Ministry of Natural ResourcesBeijing 100081China

The evolution of sea surface temperature(SST)in the tropical Pacific during 2020–2021 indicates a second-year cooling in late 2021 again,following the 2020 La Niña *** physical explanations are still lacking,and there is a clear need to understand the underlying processes *** data and reanalysis products are used to describe the characteristics and spatiotemporal evolution of upper-ocean thermal anomalies;an intermediate coupled model(ICM)is also used to perform numerical experiments to confirm these observation-based *** evolution of subsurface thermal anomalies is critically important to that of SST in the central-eastern equatorial Pacific;the effects of the former on the latter can be well represented by the temperature of subsurface waters entrained into the mixed layer(Te),a field that reflects a subsurface forcing on *** SST evolution is sensitively dependent on the intensities of the local effect associated with Te anomalies in the eastern equatorial Pacific and the remote effect associated with subsurface anomalies from the western *** early-and mid-2021,a competition was present between these local and remote effects associated with Te *** the remote warming effect dominates the local cooling effect,the cold SST condition in the east is likely to turn into neutral and warm conditions;otherwise,it tends to *** addition,the negative Te anomalies were sustained and enhanced by off-equatorial processes due to equatorial wave reflections at the eastern boundary associated with the 2020 La Niña *** SST evolution in mid-2021 corresponded to a situation in which the warming effect associated with positive subsurface thermal anomalies from the west were not strong enough to counteract the local cooling effect associated with negative anomalies in the *** due course,cold SST anomalies in the east developed again and the second-year cooling reoccurred in late 2021,with a turning point in

关键词： Prolonged La Niña evolution in 2020-2021 Subsurface effect on SST Remote and local processes Modeling experiments

Seasonal and spatial distributions of euphotic zone and longterm variations in water transparency in a clear oligotrophic Lake Fuxian, China

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Journal of Environmental Sciences 2018年第10期30卷 185-197页

作者： Qichao zhou Yunlin Zhang Kaidi Li licheng Huang Fengle Yang Yuanyang zhou Junjun Chang Taihu Laboratory for Lake Ecosystem Research State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed Yunnan Institute of Environmental Science(Kunming China International Research Center for Plateau Lake) School of Ecology and Environmental Science Yunnan University

To assess the seasonal and spatial variations and long-term trends in water optical properties in Lake Fuxian, investigations based on field work in four seasons and a long-term analysis of data from 1980 to 2014 were conducted. The results show that there was no significant variation in the euphotic depth（Z（eu）） across the four seasons, and no significant correlations between Z（eu） and potential influencing factors in seasons other than summer, suggesting that the water itself may be a major factor regulating the Z（eu）in general. Nevertheless, significant differences in Z（eu） between the north region（NR） and the south region（SR） were observed in all seasonal tests except spring. This finding relates to a higher abundance of chromophoric dissolved organic matter（CDOM） in the NR due to runoff, especially in the rainy seasons（summer and autumn）.CDOM and its terrigenous component had an important impact on Z（eu）in summer, with the highest precipitation, and impacts from suspended solids and non-algal particles were also found in the NR in summer. The Secchi disk depth in the lake decreased clearly over the years,with significantly negative correlations with the increasing permanganate index and air temperature, implying that organic contaminants（CDOM and/or phytoplankton） are important regulators of water transparency. We estimate that the combined effects of climate warming and changes in land use and land cover are also indirect regulating factors. These findings should be considered in the protection of Lake Fuxian, owing to the importance of light penetration in aquatic ecosystems.

关键词： Photosynthetic active radiation Diffuse attenuation coefficient Euphotic depth Secchi disk depth Chromophoric dissolved organic matter Yunnan-Guizhou Plateau