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Inner damage identification and residual strength assessment of a 3D printed tunnel with marble-like cementitious materials using piezoelectric transducers

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第4期15卷 838-851页

作者： GuoWEI Ma Chen Huang Junfei Zhang School of Civil and Transportation Engineering Hebei University of TechnologyTianjin300401China College of Architecture and Civil Engineering Beijing University of TechnologyBeijing100124China

Quantitative damage identification of surrounding rock is important to assess the current condition and residual strength of underground tunnels.In this work,an underground tunnel model with marble-like cementitious materials was first fabricated using the three-dimensional(3D)printing technique and then loaded to simulate its failure mode in the laboratory.Lead zirconate titanate piezoelectric(PZT)transducers were embedded in the surrounding rock around the tunnel in the process of 3D printing.A 3D monitoring network was formed to locate damage areas and evaluate damage extent during loading.Results show that as the load increased,main cracks firstly appeared above the tunnel roof and below the floor,and then they coalesced into the tunnel boundary.Finally,the tunnel model was broken into several parts.The resonant frequency and the peak of the conductance signature firstly shifted rightwards with loading due to the sealing of microcracks,and then shifted backwards after new cracks appeared.An overall increase in the root-mean-square deviation(RMSD)calculated from conductance signatures of all the PZT transducers was observed as the load(damage)increased.Damage-dependent equivalent stiffness parameters(ESPs)were calculated from the real and imaginary signatures of each PZT at different damage states.Satisfactory agreement between equivalent and experimental ESP values was achieved.Also,the relationship between the change of the ESP and the residual strength was obtained.The method paves the way for damage identification and residual strength estimation of other 3D printed structures in civil engineering.

关键词： Piezoelectric(PZT)transducers Three-dimensional(3D)printed tunnel Electro-mechanical impedance(EMI) method Equivalent stiffness parameter(ESP) Residual strength

Optimal Configuration Planning of Multi-energy Microgrid Based on Source-load-temperature Scenarios Deep Joint Generation

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CSEE Journal of Power and Energy Systems 2023年第3期9卷 1090-1102页

作者： Nantian Huang Wenting Wang GuoWEI Cai School of Electrical Engineering Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology(Northeast Electric Power University)Jilin 132012China

An optimal configuration method of a multi-energy microgrid system based on the deep joint generation of sourceload-temperature scenarios is proposed to improve the multienergy complementation and the reliability of energy supply in extreme scenarios.First,based on the historical meteorological data,the typical meteorological clusters and extreme temperature types are obtained.Then,to reflect the uncertainty of energy consumption and renewable energy output in different weather types,a deep joint generation model using a radiation-electric load-temperature scenario based on a denoising variational autoencoder is established for each weather module.At the same time,to cover the potential high energy consumption scenarios with extreme temperatures,the extreme scenarios with fewer data samples are expanded.Then,the scenarios are reduced by clustering analysis.The normal days of different typical scenarios and extreme temperature scenarios are determined,and the cooling and heating loads are determined by temperature.Finally,the optimal configuration of a multi-energy microgrid system is carried out.Experiments show that the optimal configuration based on the extreme scenarios and typical scenarios can improve the power supply reliability of the system.The proposed method can accurately capture the complementary potential of energy sources.And the economy of the system configuration is improved by 14.56%.

关键词： Deep joint generation denoising variational autoencoders multi-energy microgrid system optimal configuration planning

Oil Crops:A Potential Source of Biodiesel

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Engineering 2023年第10期29卷 39-41页

作者： Zhenhui Yan GuoWEI Li Shubo Wan Institute of Crop Germplasm Resources Shandong Academy of Agricultural SciencesJinan 250100China Shandong Provincial Key Laboratory of Crop Genetic Improvement Ecologyand PhysiologyJinan 250100China College of Agriculture Hunan Agricultural UniversityChangsha 410127China

1.Introduction Oil crops such as soybeans,sunflower,canola,rapeseed,and peanuts play a vital role in the agricultural economy,second only to food crops in terms of area and yield.Vegetable oil is known for its high energy density,containing approximately 2.25 times more calories per unit mass than carbohydrates or protein.Therefore,vegetable oil is an important source of energy and provides a variety of fatty acids necessary for human health.

关键词： crops vital soybean

IHVFL: a privacy-enhanced intention-hiding vertical federated learning framework for medical data

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Cybersecurity 2024年第2期7卷 96-112页

作者： Fei Tang Shikai Liang GuoWEI Ling Jinyong Shan College of Computer Science and Technology Chongqing University of Posts and TelecommunicationsNo.2Chongwen RoadNan'an DistrictChongqing 400065China School of Cyber Security and Information Law Chongqing University of Posts and TelecommunicationsChongqing 400065China sudo Technology Co. LTD.Beijing 100083China

Vertical Federated Learning(VFL)has many applications in the field of smart healthcare with excellent performance.However,current VFL systems usually primarily focus on the privacy protection during model training,while the preparation of training data receives little attention.In real-world applications,like smart healthcare,the process of the training data preparation may involve some participant's intention which could be privacy information for this partici-pant.To protect the privacy of the model training intention,we describe the idea of Intention-Hiding Vertical Feder-ated Learning(IHVFL)and illustrate a framework to achieve this privacy-preserving goal.First,we construct two secure screening protocols to enhance the privacy protection in feature engineering.Second,we implement the work of sample alignment bases on a novel private set intersection protocol.Finally,we use the logistic regression algorithm to demonstrate the process of IHVFL.Experiments show that our model can perform better efficiency(less than 5min)and accuracy(97%)on Breast Cancer medical dataset while maintaining the intention-hiding goal.

关键词： Medical data Vertical federated learning Privacy-presserving Intention-hiding Logistic regression

Environmental correlates of sedentary behaviors and physical activity in Chinese preschool children:A cross-sectional study

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Journal of Sport and Health Science 2022年第5期11卷 620-629页

作者： Congchao Lu Tong Shen GuoWEI Huang Eva Corpeleijn School of Public Health Tianjin Medical UniversityTianjin 300070China Department of Epidemiology University Medical Center GroningenUniversity of GroningenGroningen9700 RBthe Netherlands Tianjin Key Laboratory of Environment Nutrition and Public HealthCenter for International Collaborative Research on EnvironmentNutrition and Public HealthTianjin 300070China Tianjin University Kindergarten Tianjin UniversityTianjin 300072China Department of Nutrition and Food Science School of Public HealthTianjin Medical UniversityTianjin 300070China

Objective:This cross-sectional study examined environmental correlates of sedentary behavior(SB) and physical activity(PA) in preschool children in the urban area of Tianjin,China.Methods:Data were collected from the Physical Activity and Health in Tianjin Chinese Children study,involving healthy children 3-6 years old and their families.In all children(n=980),leisure-time SB(LTSB) and leisure-time PA(LTPA) were reported in min/day by parents.In a subgroup(n=134),overall sedentary time,light PA,and moderate-to-vigorous PA(MVP A) were objectively measured using ActiGraph accelerometry(>3 days,>10 h/day).Environmental correlates were collected using a questionnaire that included home and neighborhood characteristics(e.g.,traffic safety,presence of physical activity facilities) and children’s behaviors.Potential correlates were identified using linear regression analysis.Results:Multiple linear regression analysis showed that "having grandparents as primary caregivers"(βs and 95% confidence intervals(95%CIs)for overall sedentary time:29.7(2.1-57.2);LTSB(In):0.19(0.11-0.28)) and "having a television(for LTSB(In):0.13(0.00-0.25)) or computer(for LTSB(ln):0.13(0.03-0.23) in the child’ s bedroom" were both associated with higher SB.Furthermore, "having grandparents as primary caregivers" was associated with less MVPA(β(95%CI):-7.6(-14.1 to-1.2)),and "active commuting to school by walking" correlated with more MVPA(β(95%CI):9.8(2.2-17.4)).The path model showed that "more neighborhood PA facilities close to home" was indirectly related to higher LTPA(In),which was partly mediated by "outdoor play"(path coefficients(95%CI):0.005(0.002-0.008)) and "going to these facilities more often"(path coefficients(95%CI):0.013(0.008-0.01 8)).Traffic safety was not a correlate.Conclusion:Family structure and media exposure in the home maybe important factors in shaping preschoolers’ PA patterns.Built environmental correlates could indirectly influence preschoolers’ LTPA through parental help with engaging in active behaviors.

关键词： Active commuting Built environment Family structure Media exposure Traffic safety

Advanced TEM Characterization for Single-atom Catalysts:from Ex-situ Towards In-situ

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Chemical Research in Chinese Universities 2022年第5期38卷 1172-1184页

作者： WANG GuoWEI KE Xiaoxing SUI Manling Beijing Key Laboratory of Microstructure and Properties of Solids Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124P.R.China

Clean energy innovation has triggered the development of single-atom catalysts(SACs)due to their excellent catalytic activity,high tunability and low cost.The success of SACs for many catalytic reactions has opened a new field,where the fundamentals of catalytic property-structure relationship at atomic level await exploration,and thus raises challenges for structural characterization.Among the characterization techniques for SACs,aberration-corrected transmission electron microscopy(TEM)has become an essential tool for direct visualization of single atoms.In this review,we briefly summarize recent studies on SACs using advanced TEM.We first introduce TEM methods,which are particularly important for SACs characterization,and then discuss the applications of advanced TEM for SAC characterization,where not only atomic dispersion of single atoms can be studied,but also the distribution of elements and the valence state with local coordination can be resolved.We further extend our review towards in-situ TEM,which has increasing importance for the fundamental understanding of catalytic mechanism.Perspectives of TEM for SACs are finally discussed.

关键词： Single-atom catalyst Transmission electron microscopy(TEM) Scanning transmission electron microscopy(STEM) Electron energy loss spectroscopy(EELS) Energy dispersive X-ray spectroscopy(EDX) In-situ TEM

Anodic dissolution mechanism of TA15 titanium alloy during counter-rotating electrochemical machining

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Science China(Technological Sciences) 2022年第6期65卷 1253-1262页

作者： CAO WenJian WANG DengYong CUI GuoWEI ZHU Di College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology Nanjing 210016China

Counter-rotating electrochemical machining(CRECM)is a novel shaping method with advantages in processing revolving parts,especially engine casings.However,few researchers have studied the anodic behaviour of the counter-rotating state.This paper aims to analyse the anode dissolution behaviour of TA15 and obtain desired surface qualities in CRECM.The anodic characteristics were measured by polarization and cyclic voltammetry curves,and the passive-trans passive behaviour of TA15 was revealed.The electrode surface structures at different stages were analysed using electrochemical impedance spectroscopy(EIS),and a quantitative dissolution model was established to illustrate the electrochemical dissolution and structural evolution of the revolving surfaces.A series of CRECM experiments were conducted,and three stages(pitting corrosion,pitting expansion,and smoothing)were detected according to the current signals.In the first stage,an oxide film with small pores was formed initially on the metal surface when exposed to air.This air-formed oxide film was broken down locally during the electrochemical reaction process,resulting in the occurrence of pitting.With the increase of electricity,the oxide layer became thinner,and the pitting areas expanded and began to connect with each other.In this stage,the surface quality was poor owing to the uneven material dissolution.When the amount of electricity approximately reached a constant,the oxide layer was completely removed,and a very thin salt film was generated at the metal-electrolyte interface.In this stage,the material was dissolved uniformly,and the surface was smooth without pitting corrosion.Based on the obtained results,anode workpieces with grid-like convex structures were fabricated using CRECM.Both the revolving surface and the sidewalls of the convex structures can be controlled from pitting to smoothness.

关键词： counter-rotating electrochemical machining(CRECM) anode dissolution behaviour current signal quantitative model TA15 titanium alloy

Ultrafast dynamics of photoexcited carriers and coherent phonons in ultrathin Bi;Te;thermoelectric films

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Science China(Physics,Mechanics & Astronomy) 2022年第1期65卷 71-77页

作者： Zemin Xu Jiandong Yao GuoWEI Yang Tianshu Lai State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-sen UniversityGuangzhou 510275China State Key Laboratory of Optoelectronic Materials and Technologies Nanotechnology Research CenterSchool of Materials Science&EngineeringSun Yat-sen UniversityGuangzhou 510275China

The ultrafast dynamics of photoexcited carriers and coherent phonons in ultrathin Bi;Te;thermoelectric films are studied through transient differential transmission spectroscopy.An ultralow frequency coherent optical phonon at 0.16 THz emerges,especially in ultrathin films,and it is ascribed to interlayer breathing modes.It can divide the ultrathin films into two groups which have outof-phase vibration along the normal of a film plane,causing a destructive interference between in-plane propagating thermal waves in the two groups of quintuple layers,and thus possibly reducing the thermal conductivity of the ultrathin films.The excitation power dependence of ultrafast dynamics reveals carrier-carrier scattering dominating thermalization,which provides a microscopic understanding of the reported high electrical conductivity and anomalously high power factor of ultrathin Bi;Te;films at room temperature.

关键词： electron-electron interactions coherent phonons carrier dynamics thermoelectric effects

Impacts of CO2 elevation on the physiology and seed quality of soybean

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Plant Diversity 2020年第1期42卷 44-51页

作者： GuoWEI Zheng Jia Chen Weiqi Li College of Chinese Material Medica Yunnan University of Chinese MedicineKunmingYunnanPeople's Republic of China Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnanPeople's Republic of China Yunnan Key Laboratory of Dai and Yi Medicines Yunnan University of Chinese MedicineKunmingYunnanPeople's Republic of China

Understanding the responses of crops to elevated atmospheric carbon dioxide concentrations(E[CO2])is very important in terms of global food supplies.The present study investigates the effects of CO2 enrichment(to 800μmol mol^-1)on the physiology of soybean plants and the nutritional value of their seeds under growth chamber conditions.The photosynthesis of soybean was significantly promoted by E[CO2]at all growth stages,but leaf area and specific leaf weight were not affected.The levels of mineral elements in the leaves decreased under EICO2J.The soil properties after soybean cultivation under E[CO2]were not affected,except for a decrease in available potassium.Moreover,the levels of soluble sugars in the seeds were not affected by E[CO2].but the levels of natural antioxidants decreased.In addition,the level of oleic acid decreased under E[CO2].However,levels of fatty acid peroxidation and saturation were maintained.In conclusion.E[CO2] appears to have positive effects on the growth of cultivated soybean plants,but its influence on the nutritional values of soybean seeds is complex.Copyright?2019 Kunming Institute of Botany.Chinese Academy of Sciences.

关键词： CO2 elevation Isoflavone Tocopherol Fatty acid Mineral element