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A review of deep learning methods for pixel-level crack detection

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第6期9卷 945-968页

作者： Hongxia Li Weixing wang mengfei wang Limin Li Vivian Vimlund School of Information Engineering Chang'an UniversityXi'an 710064China School of Computer Baoji University of Arts and SciencesBaoji 721013China School of Electrical and Electronic Engineering Wenzhou UniversityWenzhou 325035China Department of Computer Science and Technology Linkoping UniversityLinköpingSweden

Cracks are a major sign of aging transportation *** detection and repair of cracks is the key to ensuring the overall safety of the transportation *** recent years,due to the remarkable success of deep learning(DL)in the field of crack detection,many researches have been devoted to developing pixel-level crack image segmentation(CIS)models based on DL to improve crack detection accuracy,but as far as we know there is no review of DL-based CIS methods *** address this gap,we present a comprehensive thematic survey of DL-based CIS *** review offers several contributions to the CIS ***,more than 40 papers of journal or top conference most published in the last three years are identified and collected based on the systematic literature review ***,according to the backbone network architecture of the models proposed in them,they are grouped into 10 topics:FCN,U-Net,encoder-decoder model,multi-scale,attention mechanism,transformer,two-stage detection,multi-modal fusion,unsupervised learning and weakly supervised learning,to be ***,our survey focuses on discussing strengths and limitations of the models in each topic so as to reveal the latest research progress in the CIS ***,publicly accessible data sets,evaluation metrics,and loss functions that can be used for pixel-level crack detection are systematically introduced and summarized to facilitate researchers to select suitable components according to their own research ***,we discuss six common problems and existing solutions to them in the field of DL-based CIS,and then suggest eight possible future research directions in this field.

关键词： Crack image segmentation Crack detection Convolutional neural networks Deep learning Systematic literature review

基于非线性色散方程组的全柔性航天器的动力学分析

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空间控制技术与应用 2024年第4期50卷 26-36页

作者：袁泉魏春岭张军万强邹奎王梦菲中国空间技术研究院杭州中心杭州310024 北京控制工程研究所北京100094 空间智能控制技术全国重点实验室北京100094

空间太阳能电站等大型结构由于采用轻质材料且结构尺寸大,呈全柔性状态,即不存在刚性构架,使得传统的中心刚体附加截断模态的方法在处理动力学问题时会出现显著的误差.从连续空间的角度对空间太阳能电站的动力学性质进行分析,以确定不... 详细信息

空间太阳能电站等大型结构由于采用轻质材料且结构尺寸大,呈全柔性状态,即不存在刚性构架,使得传统的中心刚体附加截断模态的方法在处理动力学问题时会出现显著的误差.从连续空间的角度对空间太阳能电站的动力学性质进行分析,以确定不同条件下起主导作用的动力学行为,为控制系统设计提供足够准确的模型简化原则.将空间太阳能电站看作平面内运动的自由边界非线性梁,根据Hamilton原理得到描述局部弹性运动与全局刚性运动的动力学模型.分析小变形情形下动力学方程在给定初始条件下的稳态解及其渐进性,讨论模态解或考虑了波动效应的色散解与结构尺寸、刚度等参数的关系,初步分析有限变形情形下可能出现的动力学行为,如动力刚化、非线性正规模态和孤立子解.总结空间太阳能电站在不同结构参数或运动条件下的动力学模型简化原则.对关键要素分析结果进行数值仿真,以此验证了理论分析结果.

关键词：柔性航天器大范围自由运动动力刚化色散性简化模型

华北落叶松林不同坡位土壤含水量对降雨的响应

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森林与环境学报 2024年第4期44卷 357-366页

作者：王梦飞刘泽彬于松平徐丽宏郭建斌北京林业大学水土保持学院北京100083 中国林业科学研究院森林生态环境与自然保护研究所国家林业和草原局森林生态环境重点实验室北京100091

为明确森林坡面不同坡位土壤含水量对降雨的响应差异,选取六盘山半湿润区华北落叶松林典型坡面为研究对象,于2022年5—10月连续观测降雨等气象因子,以及不同坡位(坡上、坡中和坡下)0~60 cm根系层土壤含水量变化,分析生长季土壤含水量对... 详细信息

为明确森林坡面不同坡位土壤含水量对降雨的响应差异,选取六盘山半湿润区华北落叶松林典型坡面为研究对象,于2022年5—10月连续观测降雨等气象因子,以及不同坡位(坡上、坡中和坡下)0~60 cm根系层土壤含水量变化,分析生长季土壤含水量对不同降雨事件的响应及其坡位差异。结果表明:土壤含水量存在坡位差异,其平均值表现为坡上>坡中>坡下,且土壤含水量的波动在坡中最大;降雨对土壤含水量的补给有坡位差异,降雨补给阈值在坡中最小,为1.9 mm,在坡下最大,为2.3 mm;不同土层土壤含水量对降雨的响应有坡位差异,在小雨事件中,各坡位0~20 cm土层响应速度最快,但在中雨和大雨事件中,坡中和坡上40~60 cm土层土壤含水量对降雨的响应早于20~40 cm土层,表明在坡中和坡上土壤中可能存在优先流。研究结果对于理解坡面土壤水分运移及其再分配有重要意义。

关键词：华北落叶松林土壤含水量坡位差异降雨响应

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柔索驱动单元的模型辨识与控制器设计

实验室研究与探索 2024年第3期43卷 18-22,45页

作者：邹宇鹏张宗源王梦菲张际平来小靖王新庆中国石油大学(华东)机电工程学院山东青岛266580

针对并联柔索驱动机器人力场模拟应用场景下驱动单元的力伺服控制系统设计,基于Links半物理仿真环境,运用Matlab System Identification工具箱,对柔索驱动单元系统数学模型进行模型辨识,并对系统的不确定性进行辨识。结果表明,考虑柔索... 详细信息

针对并联柔索驱动机器人力场模拟应用场景下驱动单元的力伺服控制系统设计,基于Links半物理仿真环境,运用Matlab System Identification工具箱,对柔索驱动单元系统数学模型进行模型辨识,并对系统的不确定性进行辨识。结果表明,考虑柔索驱动单元的不确定性因素后实际系统模型与理论模型相吻合,且系统理论模型具有较高的可靠性。在可靠的理论模型基础上,对柔索驱动单元进行控制器设计,并验证了模型辨识方法的有效性。基于模型辨识的控制器设计方法可以推广到其他类型系统的模型辨识。

关键词：模型辨识力伺服系统半物理仿真柔索驱动单元

Mesoporous carbon layer encapsulated SnSe nanosheets via covalent bonds for high-performance sodium ion batteries

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ChemPhysMater 2023年第2期2卷 164-171页

作者： mengfei wang Liang Yang Maocheng Liu School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals Lanzhou University of TechnologyLanzhou 730050China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China

Sodium ion batteries(SIBs)have been widely studied because of their low cost,low standard redox potential,and abundant sodium ***,the structural rupture during the Na+insertion/extraction processes and the poor conductivity of the anode material limit its cycling stability and rate ***,SnSe@C was prepared by high-temperature annealing with dopamine hydrochloride as the carbon source,while SnSe was prepared by a protein reduction *** carbon layer not only works as a protective layer to limit the volume expansion of SnSe and reduce the dissolution of Na 2 Se and poly-selenides generated during the discharge process in the electrolyte,but also as a conductive matrix to expedite electron transfer,thereby boosting the cycling stability and rate capability of SnSe@*** from the above advantages,SnSe@C exhibits a specific capacity of 211.3 mAh g^(−1) at 0.1 A g^(−1) after 110 cycles and outstanging rate capability(210.1 mAh g^(−1) at 5.0 A g^(−1) and capacity retention rate of 63.2%from 0.1 to 1.0 A g^(−1)).This study not only proposes an idea for promoting the cycling stability and rate capability of SnSe,but also paves the way for providing anodic materials with a stable structure for SIBs.

关键词： Sodium ion batteries Protein reduction method SnSe nanosheets High conductivity

Pavement crack image acquisition methods and crack extraction algorithms:A review

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第6期6卷 535-556页

作者： Weixing wang mengfei wang Hongxia Li Heng Zhao Kevin wang Changtao He Jun wang Sifan Zheng Jiabin Chen School of Information Engineering Chang an UniversityXi'an 710064China Royal Institute of Technology Stockholm 10044Sweden Sichuan Jiuzhou Electric Group Co. LtdMianyang 621000China School of Electronics and Information Engineering Sichuan UniversityChengdu 610064China Intelligent Manufacturing Engineering College Liming Vocational UniversityQuanzhou 362000China

The extraction of pavement cracks is always a hard task in image *** airport and road construction,cracking is the main factor for pavement damage,which can decrease the quality of pavement and affect transportation *** also exist in other artificial or natural objects,such as buildings,bridges,tunnels,*** all the object images,pavement crack images are the most complex,so the image processing and analysis for them is harder than other crack *** the early image acquisition based on photography technology to the current 3 D laser scanning technology,the pavement crack image acquisition technology is becoming more convenient and efficient,but there are still challenges in the automatic processing and recognition of cracks in *** the early global thresholding to deep learning algorithms,the research for crack extraction has been developed for about 40 *** are many methods and algorithms that are satisfactory in pavement crack applications,but there is no standard until ***,in order to know the developing history and the advanced research,we have collected a number of literature in this research topic for summarizing the research artwork status,and giving a review of the pavement crack image acquisition methods and2 D crack extraction ***,for image acquisition methods and pavement crack image segmentation,more detailed comparison and discussions are made.

关键词： Highway engineering Pavement crack Image acquisition Image processing Crack extraction

Thermoelectric enhancement of p-type Si_(80)Ge_(20) alloy via co-compositing of dual oxides:Respective regulation for power factor and thermal conductivity byβ-Ga_(2)O_(3) and SiO_(2) aerogel powders

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Journal of Advanced Ceramics 2023年第2期12卷 228-241页

作者： Huajun LAI Ying PENG mengfei wang Runze SHI Junliang CHEN Chengyan LIU Yifeng wang Lei MIAO Haiqiao WEI Key Laboratory of Information Material Ministry of EducationGuangxi Key Laboratory of Information MaterialSchool of Materials Science and EngineeringGuilin University of Electronic TechnologyGuilin 541004China Guangxi Key Laboratory of Precision Navigation Technology and Application School of Information and CommunicationGuilin University of Electronic TechnologyGuilin 541004China School of Physical Science and Technology Guangxi UniversityNanning 530004China College of Materials Science and Engineering Nanjing Tech UniversityNanjing 210009China State Key Laboratory of Engines Tianjin UniversityTianjin 300072China

Si-based thermoelectric(TE)materials are exhibiting remarkable perspectives in self-energized applications with their special ***,the relatively high total thermal conductivity(κ)prevents their TE ***,a strategy of co-compositing dual oxides was implemented for enhancing the TE properties of p-type Si_(80)Ge_(20) *** Ga2O_(3) was demonstrated to enhance the power factor(PF)due to the crystallization-induced effect of produced Ga by decomposition on SiGe *** with compositing SiO_(2) aerogel(a-SiO_(2))powder,not only introduced the fine amorphous inclusions and decreased the grain size of host matrix,but also various nano morphologies were formed,i.e.,nano inclusions,precipitations,twin boundaries(TBs),and *** with the eutectic Ge,hierarchical scattering centers impeded the phonon transport comprehensively(decreasing the phonon group velocity(a v)and relaxation time)for reducing the lattice-induced thermal conductivity(lκ).As a result,a minimumκof 2.38 W·m^(−1)·K^(−1) was achieved,which is significantly dropped by 32.6%in contrast with that of the pristine ***,a maximal dimensionless figure of merit(ZT)of 0.9 was achieved at 600℃,which is better than those of most corresponding oxide-composited Si-based bulks.

关键词： thermoelectric(TE)materials SiGe Ga_(2)O_(3) SiO_(2)aerogel(a-SiO_(2)) average velocity of sound hierarchical scattering

不同坏死病灶位置对非创伤性股骨头坏死自然病程的影响

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中国组织工程研究 2024年第6期28卷 917-921页

作者：赵汝顺郝阳泉许鹏郑鑫姜永宏张玉婷王孟飞鲁超西安交通大学附属红会医院陕西省西安市710054 陕西中医药大学陕西省咸阳市712000 中南大学湘雅公共卫生学院湖南省长沙市410078

背景:非创伤性股骨头坏死若股骨头发生塌陷将会显著影响患者的正常生活,因此需要使用恰当方式去评估股骨头塌陷风险,进而采取针对性措施延缓股骨头塌陷进程。目的:分析不同坏死病灶位置下早期股骨头坏死(未塌陷时)的自然病程发展规律。... 详细信息

背景:非创伤性股骨头坏死若股骨头发生塌陷将会显著影响患者的正常生活,因此需要使用恰当方式去评估股骨头塌陷风险,进而采取针对性措施延缓股骨头塌陷进程。目的:分析不同坏死病灶位置下早期股骨头坏死(未塌陷时)的自然病程发展规律。方法:选择2016年10月至2017年10月在西安交通大学附属红会医院门诊确诊的早期非创伤性股骨头坏死患者121例(191髋),门诊随访5年后,观察在不同JIC分型下股骨头坏死塌陷情况及各分型之间的股骨头塌陷风险系数,计算随访期间股骨头坏死塌陷率。结果与结论:(1)纳入191髋,随访期间股骨头塌陷86髋,股骨头总塌陷率为45.0%;在影响因素里,年龄、ARCO分期、JIC分型为股骨头塌陷的主要影响因素(P0.05);(2)纳入的191髋中,随访期间JIC分型A型、B型、C1型、C2型的股骨头总塌陷率分别为11.1%(2/18),30.2%(16/53),52.4%(43/82),65.8%(25/38),各分型间股骨头总塌陷率比较差异有显著性意义(P0.05);在ARCOⅡ期患髋中,JIC A型、B型、C1型及C2型的股骨头塌陷率分别为1.2%,19.5%,50.0%,29.3%,各分型间股骨头塌陷率比较差异有显著性意义(P<0.05);(4)随访期间,第1-5年内的股骨头塌陷率分别为29.3%,7.9%,4.7%,2.6%,0.5%;(5)结果显示,对于早期非创伤性股骨头坏死,1年内股骨头塌陷的风险大,骨坏死病灶位置影响着股骨头塌陷的风险,临床治疗中应考虑到病灶位置对疾病预后的影响。

关键词：非创伤性股骨头坏死股骨头塌陷病灶位置 JIC分型自然病程

Implantable probe with integrated reference electrode for in situ neural signal and calcium ion monitoring

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Bio-Design and Manufacturing 2024年第4期7卷 591-595页

作者： Junyu Xiao mengfei Xu Longchun wang Bin Yang Jingquan Liu National Key Laboratory of Advanced Micro and Nano Manufacture Technology Shanghai Jiao Tong UniversityShanghai 200240China Department of Micro/Nano Electronics Shanghai Jiao Tong UniversityShanghai 200240China

Monitoring the electrophysiology activity of neurons and blood calcium signals can enable a better understanding of disease-related neural system ***,currently,in situ calcium ion monitoring tools are scarce and exhibit low integration and limited *** this letter,we propose an implantable probe with an integrated in situ Ag/AgCl reference electrode(ISA/ARE)that can monitor action potential(AP)and Ca^(2+) concentrations.

关键词： neural electrode enable