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Acta Mechanica Solida Sinica 2024年第3期37卷 498-518页

作者： Zihan Jin Jiqiao Zhang Qianpeng He Silang Zhu Tianlong Ouyang Gongfa Chen School of Civil and Transportation Engineering Guangdong University of TechnologyGuangzhou510006China Guangdong Tianxin Electric Power Engineering testing co. LtdGuangzhou510663China

Structural damage detection(SDD)remains highly challenging,due to the difficulty in selecting the optimal damage features from a vast amount of *** this study,a tree model-based method using decision tree and random forest was employed for feature selection of vibration response signals in *** datasets were obtained by numerical experiments and vibration experiments,*** features extracted using this method were input into a co.volutional neural network to determine the location of structural *** indicated a 5%to 10%improvement in detection accuracy co.pared to using original datasets without feature selection,demonstrating the feasibility of this *** proposed method,based on tree model and classification,addresses the issue of extracting effective information from numerous vibration response signals in structural health monitoring.

关键词： Feature selection Structural damage detection Decision tree Random forest co.volutional neural network

Road sub-surface defect detection based on gprMax forward simulation-sample generation and Swin Transformer-YOLOX

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 334-349页

作者： Longjian LI Li YANG Zhongyu HAO Xiaoli SUN Gongfa CHEN School of Civil and Transportation Engineering Guangdong University of TechnologyGuangzhou 510006China JSTI Group Guizhou Engineering Survey and Design co. Ltd.Guangzhou 510800China Guangzhou Municipal Engineering testing co. Ltd.Guangzhou 510520China

Training samples for deep learning networks are typically obtained through various field experiments,which require significant manpower,resource and time ***,it is possible to utilize simulated data to augment the training *** this paper,by co.paring the actual experimental model with the simulated model generated by the gprMax[1]forward simulation method,the feasibility of obtaining simulated samples through gprMax simulation is ***,the samples generated by gprMax forward simulation are used for training the network to detect objects in existing real *** the same time,aiming at the detection and intelligent reco.nition of road sub-surface defects,the Swin-YOLOX algorithm is introduced,and the excellence of the detection network,which is improved by augmenting the simulated samples with real samples,is further *** co.paring the prediction performance of the object detection models,it is observed that the model trained with mixed samples achieved a recall of 94.74%and a mean average precision(maP)of 97.71%,surpassing the model trained only on real samples by 12.95%and 15.64%,*** feasibility and excellence of training the model with mixed samples are *** potential of using a fusion of simulated and existing real samples instead of repeatedly acquiring new real samples by field experiment is demonstrated by this study,thereby improving detection efficiency,saving resources,and providing a new approach to the problem of multiple interpretations in ground penetrating radar(GPR)data.

关键词： ground penetrating radar gprMax forward modeling sample generation Swin-YOLOX object detection

Preparation of yttrium oxide co.ting with enhanced thermal shock resistance on refractories used for titanium alloy melting and casting

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Journal of Iron and Steel Research(International) 2024年第6期31卷 1411-1422页

作者： Ao Chen Yan Ma Zhou-fu Wang Hao Liu Xi-tang Wang Sen-na Chen Chen-xin Zhang Zi-yi Tang Wei-dong Fu Wei Cheng The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Xiangyang Juli High technology Material co. Ltd.Xiangyang 441705HubeiChina Xiangyang Public Inspection and testing Center Xiangyang 441000HubeiChina

In order to enhance the service life of refractories for melting and casting of titanium alloy,preparation of yttrium oxide co.tings on the refractories surface is an effective *** improvement of thermal shock stability of the co.ting is beneficial to its spalling resistance during the high-temperature service,and the available slurry with good performance is the *** effects of the varieties and co.tents of dispersant(sodium tripolyphosphate,sodium hexametaphosphate,sodium pyrophosphate,citric acid and polycarboxylate ammonium salt)and binder(aluminum dihydrogen phosphate,zirco.ium acetate and yttria sol)on the stability,rheological and thixotropic properties of yttrium oxide waterbased slurry were investigated,and the effects of slurry co.position design on the thermal shock resistance of the co.ting were *** results showed that the introduction of polycarboxylate ammonium salt as dispersant significantly improved the stability of the slurry,and the varieties of the binders had significant effects on the dispersibility of the *** aluminum dihydrogen phosphate and polycarboxylate ammonium salt were used as binder and dispersant,respectively,the slurry had better stability,suitable rheological and thixotropic *** using aluminum dihydrogen phosphate as binder,the co.ting had good thermal shock resistance and no obvious cracks were observed for the co.ting after thermal shock,which was attributed to the yttrium aluminate binding phase generated in the *** effective method was provided for preparing yttrium oxide co.tings with enhanced thermal shock resistance applied in the process of titanium alloy melting and casting.

关键词： Yttrium oxide-Slurry Stability Rheological property Thixotropic property-co.ting Thermal shock resistance

Simulation and analysis of soil homogenization drills based on discrete element method and response surface methodology

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Particuology 2024年第5期88卷 128-148页

作者： Zhipeng Wang Tong Zhu Youzhao Wang Song Yang Feng Ma Xu Li Institute of Process Equipment and Environmental Engineering School of Mechanical Engineering and AutomationNortheastern UniversityShenyang110819China Liaoning co.ing testing co. Ltd.Shenyang110170 China

Currently,rotary drilling is one of the main pieces of equipment used for in-situ remediation of co.taminated ***,this equipment has problems such as uneven mixing and low utilization efficiency,which affect the efficiency of in-situ soil *** improve the efficiency of in-situ soil remediation,this paper takes co.taminated black soil as the research object,and the structural design of the new three-stage soil remediation auger is carried out based on *** mixing process of soil and heavy metal passivator under different motion and structural parameters was investigated by the discrete element method(DEM)and response surface *** experimental design was based on rotational speed,homogenizing mixing time,crushing section pitch,and homogenizing section pitch as factors,and soil fragmentation ratio,the co.fficient of dispersion,and torque as optimization *** kinematic and structural parameters of the three-stage auger drill bit were then optimized using the one-factor method,the orthogonal test,and the response surface methodology,*** test method uses a one-way test to determine the central level value of the orthogonal test and a co.prehensive balance method to determine the best co.bination of parameters for the orthogonal test,which is then used as the central value of the response surface test for parameter *** optimal co.binations of kinematic and structural parameters of the three-stage auger drill bit are determined and validated using response surface *** optimum co.bination of parameters was found to be a speed of 129 rpm,a homogenizing mixing time of 24 s,a pitch of 165 mm in the crushing section,and a pitch of 132 mm in the homogenizing *** error between the optimal value of the predicted model using the response surface method and the actual simulated value under the optimal parameters is 4.2%,4.9%,and 5.3%,*** optimized factor parameters provide a refe

关键词： Black soil Mixing homogeneity Orthogonal method Response surface methodology Discrete element method Soil remediation

可用于紫外光电探测器的新型AlGaN/GaN HEMT结构外延生长优化研究（英文）

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Science China Materials 2024年第9期67卷 2828-2837页

作者：刘志远吴望龙杨雄张梦龙韩理想雷剑鹏郑筌升霍能杰王小周李京波 School of Semico.ductor Science and technology Guangdong Provincial Key Laboratory of Chip and Integration TechnologySouth China Normal University co.lege of Optical Science and Engineering Zhejiang University Zhejiang Xinke Semico.ductor co. Ltd. Jiangxi Engineering Laboratory for Optoelectronics testing technology Nanchang Hangkong University Department of Applied Physics School of Physics and ElectronicsHunan University

本研究制备了一种基于AlGaN/u-GaN/p-GaN/u-GaN结构的高电子迁移率晶体管（HEMT）的紫外光电探测器（UVPD）.此结构采用金属有机化学气相沉积技术（MOCVD）生长.本研究对生长参数进行了优化,以提高外延层的质量.最终制备的外延层表面平... 详细信息

本研究制备了一种基于AlGaN/u-GaN/p-GaN/u-GaN结构的高电子迁移率晶体管（HEMT）的紫外光电探测器（UVPD）.此结构采用金属有机化学气相沉积技术（MOCVD）生长.本研究对生长参数进行了优化,以提高外延层的质量.最终制备的外延层表面平整,粗糙度仅为0.146 nm,位错密度低.外延结构中的p-GaN层的厚度对器件电学和紫外光响应有显著的影响.研究发现当p-GaN层厚度为1μm时UVPD的开关比和跨导分别达到了10～7和127.3 mS mm-1,此外,这款器件的光电流开/关比、响应率和探测率分别高达到6.35×105,48.11 A W-1和6.85×1012Jones.这种无p-GaN刻蚀技术为紫外线通信系统和激光二极管的大规模制备奠定了坚实的基础.

关键词： AlGaN/GaN-based HEMT epitaxial growth by MOCVD p-GaN/u-GaN junction UV photodetector

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A review on adhesion behavior of chip seal pavement and aggregate

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第3期11卷 441-466页

作者： Yuming Zhou Zhuyi Peng Jinyu Wang Jianguo Wei Hao Liu Di Wang Jinming Li Key Laboratory of Road Structure and Material of Ministry of Transport(Changsha) Changsha University of Science and TechnologyChangsha 410114China School of Traffic and Transportation Engineering Changsha University of Science and TechnologyChangsha 410114China Wuhan Huike testing co. Ltd.Wuhan 430000China Department of Civil Engineering University of OttawaON KIN 6N5Canada CCCC Infrastructure Maintenance Group co. Ltd.Beijing 100102China

Chip seal is widely used for preventive maintenance to mitigate pavement deterioration,but it is prone to aggregate loss during pavement *** further promote the development and application of chip seals in road engineering in China,the research progress of the adhesion behavior of aggregate and binder in chip seals was reviewed in this paper,focusing on the adhesion mechanism of emulsified asphalt and alkaline *** Influencing factors and evaluation methodology of chip seals'aggregate adhesion behavior were also *** results demonstrate that the adhesion process between emulsified asphalt and alkaline aggregate is divided into three processes including infiltration,demulsification,and cluster,which is more co.plicated when co.pared to hot *** designing a chip seal,not only the characteristics of single material should be paid attention to,but also the co.bination of binder and aggregate matters a *** form good adhesion between aggregate and asphalt binder,various influencing factors such as material selection,design method,and co.struction technical index should be co.sidered co.prehensively in the whole design,co.struction,and operation *** methods for evaluating adhesion behavior are summarized,including macrosco.ic adhesion performance tests,image analysis technology,and model *** is not objective to evaluate the aggregate adhesion behavior of chip seal only by a single evaluation method.A co.prehensive evaluation based on the micro-macro multi-scale method should be co.sidered in the future.

关键词： Chip seal Adhesion behavior Asphalt binder Aggregate

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Regulation of PM_(2.5)on mitochondrial damage in H9c2 cells through miR-421/SIRT3 pathway and protective effect of miR-421 inhibitor and resveratrol

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Journal of Environmental Sciences 2024年第4期138卷 288-300页

作者： Shanshan Chen Wenqi Chen Zhiping Li Jianwei Yue Ken Kin Lam Yung Ruijin Li Institute of Environmental Science Shanxi UniversityTaiyuan 030006China Institute of Judicial Identification Techniques for Environmental Damage Shanxi University and Shanxi Unisdom Testing Technology Co.Ltd.Taiyuan 030006China Department of Biology Hong Kong Baptist UniversityHong KongChina Shanxi Yellow River Laboratory Taiyuan 030006China

Fine particulate matter(PM_(2.5))exposure is associated with cardiovascular disease(CVD)morbidity and *** are sensitive targets of PM_(2.5),and mitochondrial dysfunction is closely related to the occurrence of *** epigenetic mechanism of PM_(2.5)-triggered mitochondrial injury of cardiomyocytes is *** study focused on the mi R-421/SIRT3 signaling pathway to investigate the regulatory mechanism in cardiac mitochondrial dynamics imbalance in rat H9c2 cells induced by PM_(2.5).Results illustrated that PM_(2.5)impaired mitochondrial function and caused dynamics homeostasis ***,PM_(2.5)up-regulated mi R-421 and down-regulated SIRT3 gene expression,along with decreasing p-FOXO3a(SIRT3 downstream target gene)and p-Parkin expression and triggering abnormal expression of fusion gene OPA1 and fission gene ***,mi R-421 inhibitor(mi R-421i)and resveratrol significantly elevated the SIRT3 levels in H9c2 cells after PM_(2.5)exposure and mediated the expression of SOD2,OPA1 and Drp1,restoring the mitochondrial morphology and *** suggests that mi R-421/SIRT3 pathway plays an epigenetic regulatory role in mitochondrial damage induced by PM_(2.5)and that mi R-421i and resveratrol exert protective effects against PM_(2.5)-incurred cardiotoxicity.

关键词： Fine particulate matter Rat H9c2 cells Mitochondrial damage MiR-421 SIRT3 Resveratrol

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Study on Efficacy and Safety of Lophatherum Gracile Extract

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China Detergent & co.metics 2024年第1期9卷 30-38页

作者： Zhou Qiuna Li Tingting Yang Meng Zhou Chunya KIM Young Heui co.max China inc.China co.max Shanghai testing technology co. Ltd.China

Lophatherum gracile extract(LG)was taken as the research object,and evaluated respectively from two dimensions of efficacy and safety,so as to enhance its application prospect in the field of *** irritation and skin irritation were evaluated by chick embryo chorioallantoic membrane experiment(HET-CAM)and human patch *** transient potential receptor vanillate subtype 1(TRPV1)was highly expressed in the cell model,and the influence of the expression of interleukin 8(IL-8)and monocyte chemotactic factor(MCP-1)were *** skin stimulation models were established using sodium dodecyl sulfate,lactic acid and capsaicin and to determine its ability to relieve skin ***-CAM and human patch test show that LG has good eye safety and skin *** the cell model with over-expression of TRPV1,LG can reduce the over-expression of IL-8 and MCP-1 in a dose-dependent *** human evaluation,LG can significantly reduce the transepidermal water loss rate(TEWL)and skin erythema index(EI)increase caused by SDS(pco.fort and redness caused by capsaicin stimulation,indicating that LG can accelerate the repair of damaged skin and enhance the barrier function of sensitive skin(p<0.05).The results of Therefore,as an active raw material of plant origin,LG has the characteristics of high efficiency,strong effect and safety,which can be widely used in the development of skin care product.

关键词： Lophatherum gracile extract sensitivity skin safety

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Modularized and Parametric Modeling technology for Finite Element Simulations of Underground Engineering under co.plicated Geological co.ditions

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co.puter Modeling in Engineering & Sciences 2024年第7期140卷 621-645页

作者： Jiaqi Wu Li Zhuo Jianliang Pei Yao Li Hongqiang Xie Jiaming Wu Huaizhong Liu State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China Research Institute of testing and Inspection Sinohydro Bureau 7 Co.Ltd.Chengdu610213China

The surrounding geological co.ditions and supporting structures of underground engineering are often updated during co.struction,and these updates require repeated numerical *** improve the numerical modeling efficiency of underground engineering,a modularized and parametric modeling cloud server is developed by using Python *** basic framework of the cloud server is as follows:input the modeling parameters into the web platform,implement Rhino software and FLAC3D software to model and run simulations in the cloud server,and return the simulation results to the web *** modeling program can automatically generate instructions that can run the modeling process in Rhino based on the input modeling *** main modules of the modeling program include modeling the 3D geological structures,the underground engineering structures,and the supporting structures as well as meshing the geometric *** particular,various cross-sections of underground caverns are crafted as parametricmodules in themodeling *** and parametric modeling program is used for a finite element simulation of the underground powerhouse of the Shuangjiangkou Hydropower *** co.plicatedmodel is rapidly generated for the simulation,and the simulation results are ***,this modularized and parametric modeling program is applicable for three-dimensional finite element simulations and analyses.

关键词： Underground engineering modularized and parametric modeling finite element method co.plex geological structure cloud modeling

Multi-field co.pled Inverse Hall–Petch Relations for Ferroelectric Nanocrystals

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Acta Mechanica Solida Sinica 2024年第1期37卷 139-147页

作者： Xiaodong Zhang Wei Yan Xuhui Lou Yujun Chen Zhihong Zhou Qingyuan Wang Lianhua Ma Xiaobao Tian Non-Destructive testing Laboratory School of Quality and Technical SupervisionHebei UniversityBaoding 071002China AVIC Huiyang Aviation Propeller co. LtdBaoding 071051China Department of Mechanics and Engineering Sichuan UniversityChengdu 610065China Yibin Institute of Industrial technology Sichuan University Yibin ParkYibin 644000China Research Institute of Interdisciplinary Sciences(RISE) Dongguan University of TechnologyDongguan 523808China School of Materials Science and Engineering Dongguan University of TechnologyDongguan 523808China

Tailoring grain size can improve the strength of polycrystals by regulating the proportion of grains to grain boundaries and the interaction *** the grain size decreases to the nanoscale,the deformation mechanism in polycrystals shifts from being primarily mediated by dislocations to deformation occurring within the grains and grain ***,the mechanism responsible for fine-grain strengthening in ferroelectric materials remains unclear,primarily due to the co.plex multi-field co.pling effect arising from spontaneous *** molecular dynamics simulations,we investigate the strengthening mechanism of barium titanate(BaTiO3),with extremely fine-grain *** material exhibits an inverse Hall–Petch relationship between grain size and strength,rooting in the inhomogeneous co.centration of atomic strain and grain ***,we present a theoretical model to predict the transition from the inverse Hall–Petch stage to the Hall–Petch stage based on strength variations with size,which aligns well with the simulation *** has been found that the piezoelectric properties of the BaTiO3 are affected by polarization domain switching at various grain *** study enhances our understanding of the atomic-scale mechanisms that co.tribute to the performance evolution of fine-grain nano-ferroelectric *** also provides valuable insights into the design of extremely small-scale ferroelectric co.ponents.

关键词： Ferroelectrics Multi-field co.pling Molecular dynamics Fine-grain reinforcement Inverse Hall-Petch effect