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基于极限梯度提升和探地雷达时频特征的水泥路面脱空识别

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同济大学学报（自然科学版） 2024年第1期52卷 104-114,121页

作者：张军姜文涛张云罗婷倚余秋琴杨哲长安大学公路养护装备国家工程实验室陕西西安710064 长安大学道路施工技术与装备教育部重点实验室陕西西安710064 广西北投公路建设投资集团有限公司广西南宁530028 广西交科集团有限公司广西南宁530007

针对探地雷达(GPR)数据解译依赖于人工经验,存在费时费力和主观偏差的问题,提出了基于极限梯度提升(XGBoost)和GPR时频特征的水泥路面脱空识别方法。采用正演模拟、室内试验和现场试验获得了脱空病害数据源,建立含有标签的脱空GPR数据集... 详细信息

针对探地雷达(GPR)数据解译依赖于人工经验,存在费时费力和主观偏差的问题,提出了基于极限梯度提升(XGBoost)和GPR时频特征的水泥路面脱空识别方法。采用正演模拟、室内试验和现场试验获得了脱空病害数据源,建立含有标签的脱空GPR数据集;通过重采样方法统一GPR数据采样频率,并对预处理后的GPR数据进行时频域特征提取,建立了包含18个时域和12个频域特征的数据集。以时频域特征为输入,是否存在脱空病害为输出,采用XGBoost算法构建脱空识别模型,并与随机森林(RF)和人工神经网络(ANN)算法进行对比。结果表明,模型的识别准确率排序为XGBoost(98.10%)>ANN(95.10%)>RF(93.17%),XGBoost模型识别精度最高,并能在实际路面上准确定位脱空区域。

关键词：道路养护探地雷达(GPR) 脱空病害极限梯度提升(XGBoost) 时频域特征

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基于探地雷达时频特征的水泥路面脱空识别

地下空间与工程学报 2024年第4期20卷 1334-1344页

作者：张军姜文涛余秋琴李有鑫罗婷倚长安大学道路施工技术与装备教育部重点实验室西安710064 广西北投公路建设投资集团有限公司南宁530028

脱空病害在水泥路面中不可避免,危害路面结构安全性,迫切需要建立脱空病害区域的准确定位方法。采用探地雷达(GPR)为无损检测工具,通过GPR信号时频特征的提取和正反演实验构建了脱空病害的特征数据集,将特征集进行PCA降维,以PCA主元为... 详细信息

脱空病害在水泥路面中不可避免,危害路面结构安全性,迫切需要建立脱空病害区域的准确定位方法。采用探地雷达(GPR)为无损检测工具,通过GPR信号时频特征的提取和正反演实验构建了脱空病害的特征数据集,将特征集进行PCA降维,以PCA主元为输入、正常和脱空为输出分别建立SVM和ANN脱空识别模型;在获得脱空的GPR信号上提出窗口能量法判断脱空区域的深度,在实际路面上对脱空识别进行验证。结果表明:时频特征可表征脱空病害,包含病害的部分数据集更适合用于建模识别;ANN的识别准确度优于SVM,窗口能量法可有效定位脱空区域的深度,并对噪声具有一定的鲁棒性,在室内模型中定位精度平均误差1.51%。研究结果可为路面精准养护提供科学依据。

关键词：道路工程水泥路面无损检测脱空识别探地雷达

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横州飞龙大桥主桥设计

世界桥梁 2024年第3期52卷 17-22页

作者：唐亚森罗婷倚张云王思豪刘玉擎广西北投公路建设投资集团有限公司广西南宁530022 同济大学桥梁工程系上海200092

横州飞龙大桥主桥为(100+2×185+100)m波形钢腹板连续刚构桥,主梁为单箱单室波形钢腹板组合箱梁,桥面宽13 m,中支点梁高10.9 m,跨中及边跨梁端梁高4 m。腹板采用1800型波形钢腹板,相比传统1600型腹板具有更高的整体屈曲应力;波形钢腹板... 详细信息

横州飞龙大桥主桥为(100+2×185+100)m波形钢腹板连续刚构桥,主梁为单箱单室波形钢腹板组合箱梁,桥面宽13 m,中支点梁高10.9 m,跨中及边跨梁端梁高4 m。腹板采用1800型波形钢腹板,相比传统1600型腹板具有更高的整体屈曲应力;波形钢腹板防屈曲构造采用内衬混凝土和纵、横向加劲肋混合布置的方式,减少了内衬混凝土长度,减轻了结构自重;波形钢腹板与顶板采用长孔型开孔板连接件,与底板采用外包型连接,提高了结合部施工便捷性和耐久性。主梁采用波形钢腹板悬臂自承重施工工法,先边跨后中跨合龙,采用研发的钢架吊篮与智能吊机组合的挂篮形式,提高了施工效率。

关键词：波形钢腹板连续刚构桥组合箱梁 1800型波形钢腹板加劲肋长孔型开孔板外包型连接腹板自承重施工结构设计

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水泥路面脱空区域GPR信号的时频域分析

现代雷达 2024年第1期46卷 45-51页

作者：余秋琴罗婷倚朱欣李有鑫张军刘斌广西北投公路建设投资集团有限公司广西南宁530028 公路养护装备国家工程实验室陕西西安710064 道路施工技术与装备教育部重点实验室陕西西安710064

水泥路面脱空是导致路面板块断裂的主要因素,若能及早确定脱空区域的范围,则可为水泥路面结构安全性的力学分析提供依据。以水泥路面脱空病害为研究对象,采用正演模拟方法研究了不同脱空形状以及不同填充物质对GPR(探地雷达)响应信号的... 详细信息

水泥路面脱空是导致路面板块断裂的主要因素,若能及早确定脱空区域的范围,则可为水泥路面结构安全性的力学分析提供依据。以水泥路面脱空病害为研究对象,采用正演模拟方法研究了不同脱空形状以及不同填充物质对GPR(探地雷达)响应信号的影响;采用编程软件设计了探地雷达(GPR)信号处理模块,使用连续小波变换(CWT)提取脱空区域的信号特征,对病害区域进行了3D重构;并将上述方法在构建的室内脱空模型上进行了验证。结果表明,设计的后处理软件可实现GPR信号的后处理功能,为正演和反演数据的信号分析提供有效工具;经过CWT处理后的脱空与正常路面的GPR信号在时频域差异明显,CWT图谱能量集中区域可表征脱空的深度和范围,CWT结果还可用于3D可视化分析,为解译脱空区域范围以及判断是否含水提供参考,这为GPR信号解译提供了新的处理手段。

关键词：水泥路面脱空病害探地雷达连续小波变换正演模拟

Building Fe atom–cluster composite sites using a site occupation strategy to boost electrochemical oxygen reduction

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Carbon Energy 2024年第3期6卷 276-286页

作者： tingyi Zhou Yi Guan Changjie He Lei Zhang Xueliang Sun Zhongxin Song Qianling Zhang Chuanxin He Xiantao Jiang Zhaoyan luo Wei Xing Xiangzhong Ren College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhenGuangdongChina Department of Mechanical and Materials Engineering University of Western OntarioLondonOntarioCanada State Key Laboratory of Electroanalytical Chemistry Jilin Province Key Laboratory of Low Carbon Chemical PowerChangchun Institute of Applied ChemistryChinese Academy of SciencesJilinChangchunChina

The high-temperature pyrolysis process for preparing M–N–C single-atom catalyst usually results in high heterogeneity in product structure concurrently contains multiscale metal phases from single atoms(SAs),atomic clusters to ***,understanding the interactions among these components,especially the synergistic effects between single atomic sites and cluster sites,is crucial for improving the oxygen reduction reaction(ORR)activity of M–N–C ***,herein,we constructed a model catalyst composed of both atomically dispersed FeN4 SA sites and adjacent Fe clusters through a site occupation *** found that the Fe clusters can optimize the adsorption strength of oxygen reduction intermediates on FeN4 SA sites by introducing electron-withdrawing–OH ligands and decreasing the d-band center of the Fe *** as-developed catalyst exhibits encouraging ORR activity with halfwave potentials(E1/2)of 0.831 and 0.905 V in acidic and alkaline media,***,the catalyst also represents excellent durability exceeding that of Fe–N–C SA *** practical application of Fe(Cd)–CNx catalyst is further validated by its superior activity and stability in a metalair battery *** work exhibits the great potential of synergistic effects between multiphase metal species for improvements of singleatom site catalysts.

关键词： d-band center metal clusters oxygen reduction reaction single-atom catalyst site occupations strategy

波形耐候钢腹板与混凝土顶板结合部横向抗弯疲劳性能研究

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桥梁建设 2023年第6期53卷 47-54页

作者：张云罗婷倚杨涛陈筱彬陈明宇广西北投公路建设投资集团有限公司广西南宁530029 广西大学土木建筑工程学院广西南宁530004 工程防灾与结构安全教育部重点实验室广西南宁530004

为了解波形耐候钢腹板组合箱梁桥中波形钢腹板-混凝土顶板结合部在横向弯矩下的疲劳性能,以飞龙大桥为背景,制作1个波形耐候钢腹板-混凝土顶板结合部试件,开展横向受弯疲劳试验。分析结合部试件的疲劳寿命、破坏形态、抗弯刚度变化情况... 详细信息

为了解波形耐候钢腹板组合箱梁桥中波形钢腹板-混凝土顶板结合部在横向弯矩下的疲劳性能,以飞龙大桥为背景,制作1个波形耐候钢腹板-混凝土顶板结合部试件,开展横向受弯疲劳试验。分析结合部试件的疲劳寿命、破坏形态、抗弯刚度变化情况等,并基于线性疲劳累积损伤理论,采用Eurocode 3和AASHTO规范公式评估结合部试件中相关细节的疲劳寿命。结果表明:波形耐候钢腹板-混凝土顶板结合部试件在最终疲劳破坏前经历了209.14万次的疲劳加载,可以满足结合部横向抗弯疲劳设计的要求;主要的疲劳损伤为连接波形钢腹板与钢翼缘的焊缝出现疲劳裂纹以及混凝土顶板的开裂;疲劳损伤的累积导致试件的抗弯刚度降至初始抗弯刚度的34.4%;采用Eurocode 3和AASHTO规范公式对结合部中细节进行疲劳寿命评估时,Eurocode 3规范公式计算所得的细节疲劳寿命更偏于保守。

关键词：组合梁波形耐候钢腹板结合部横向弯矩裂纹扩展疲劳寿命疲劳损伤疲劳试验

Optimal regulation of flexible loads in rural residential buildings considering mobile batteries:A case study in Shaanxi Province

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Building Simulation 2024年第7期17卷 1065-1083页

作者： Xi luo WenceShi School of Building Services Science and Engineering Xian University of Architecture and Technology(XAUAT)Xi'an 710055China State Key Laboratory of Green Building Xi'an 710055China

While the grid-connected capacity of rural household photovoltaics is increasing rapidly,achieving dynamic supply-demand matching despite fluctuations in solar energy is *** the rapid development of rural electrification,battery-powered technologies,such as electric vehicles and electric agricultural machinery,are becoming increasingly popular in rural *** this context,utilizing idle mobile batteries to assist in energy storage for rural residential buildings offers a new way to solve the problem of dynamic supply-demand *** this study,a field survey was conducted on several typical fruit-growing villages in the Central Shaanxi Plain in Shaanxi Province of *** rural households were selected to calculate the electricity loads of the residential buildings,with due consideration to the intervention of mobile *** the premise of installing 3 kW household photovoltaic systems in rural households,an economical efficiency-oriented model was built for the optimal regulation of flexible *** results were compared in the context of two patterns of electricity consumption,i.e.,unidirectional charging of mobile batteries from buildings and bidirectional charging and discharging between mobile batteries and *** bidirectional pattern significantly increased the photovoltaic consumption of typical rural households on various typical ***,during both scenarios of not implementing time-of-use and implementing time-of-use,the typical day of the winter slack farming season exhibited the best photovoltaic consumption effect among all types of typical ***,the bidirectional pattern also result in a significant increase in the annual electricity sales revenues for typical rural households.

关键词： demand-side response flexible load mobile battery household photovoltaics

Energy consumption simulations of rural residential buildings considering differences in energy use behavior among family members

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Building Simulation 2024年第8期17卷 1335-1358页

作者： Xi luo Lina Du School of Building Services Science and Engineering Xi'an University of Architecture and Technology(XAUAT)Xi'an 710055China State Key Laboratory of Green Building Xi'an 710055China

The“average occupant”methodology is widely used in energy consumption simulations of residential buildings;however,it fails to consider the differences in energy use behavior among family *** on a field survey on the Central Shaanxi Plain,to identify the energy use behavior patterns of typical families,a stochastic energy use behavior model considering differences in energy use behavior among family members was proposed,to improve the accuracy of energy consumption simulations of residential *** results indicated that the surveyed rural families could be classified into the following four types depending on specific energy use behavior patterns:families of one elderly couple,families of one middle-aged couple,families of one elderly couple and one child,and families of one couple and one ***,on typical summer days,the results of daily building energy consumption simulation obtained by the“average occupant”methodology were 25.39%and 28%lower than the simulation results obtained by the model proposed in this study for families of one elderly couple and families of one middle-aged couple,and 13.05%and 23.05%higher for families of one elderly couple and one child,and families of one couple and one *** typical winter days,for the four types of families,the results of daily building energy consumption simulation obtained by the“average occupant”methodology were 21.69%,10.84%,1.21%,and 8.39%lower than the simulation results obtained by the model proposed in this study,respectively.

关键词： typical energy use behavior pattern differences in occupant behavior building energy consumption simulation stochastic energy use behavior simulation

Switching Behavior of Cascode GaN Under Influence of Gate Driver

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1816-1833页

作者： Bin luo Guangzhao luo Sihai Li School of Automation Northwestern Polytechnical UniversityXi’an 710072China

With high-frequency,low power dissipation and high-efficiency characteristics,Gallium nitride(GaN)power devices are of significant benefit in designing high-speed motor drives,as they improve performance and reduce ***,due to the cascode structure,coupling with the parasitics in gate driver and power circuits,power converters based on cascode GaN are prone to overshoot and oscillate on switching waveforms,which may lead to serious EMC problems,or even device *** complicated structure of cascode GaN device makes the gate driver design comparatively *** analytical model of the switching process considering gate driver parameters is proposed in this *** influence of gate driver parameters on switching behavior is investigated from the perspective of switching speed,waveform overshoot,and power ***-offs among overshoot,switching speed,and power loss are discussed;guidelines to design gate driver parameters are given.

关键词： Gallium nitride(GaN) gate driver oscillation and overshoot switching characteristics