This paper discusses the performance of a proposed panelized brick veneer over steel stud backup wall system and seismic isolation connections under lateral loads. The panelized wall system was developed to address so...This paper discusses the performance of a proposed panelized brick veneer over steel stud backup wall system and seismic isolation connections under lateral loads. The panelized wall system was developed to address some shortcomings of the conventional brick veneer wall type. The details of the system are briefly introduced. The study evaluated the performance of the system under out-of-plane simulated wind loads and in-plane cyclic loads using full-scale laboratory experiments. The test setup, test specimen, test procedure, and test results are presented and the performance of the system is evaluated accordingly.展开更多
In recent years,there has been a growing global demand for carbon neutrality and energy efficiency,which are expected to become long-term trends.In the field of architecture,an effective approach to achieve this is to...In recent years,there has been a growing global demand for carbon neutrality and energy efficiency,which are expected to become long-term trends.In the field of architecture,an effective approach to achieve this is to reduce heat loss in buildings.Vacuum insulation panels(VIPs),a type of high-performance insulation material,have been increasingly utilised in the construction industry and have played an increa-singly important role as their performance and manufacturing processes continue to improve.This paper provides a review of the factors affecting the thermal conductivity of VIPs and presents a detailed overview of the research progress on core materials,barrier films,and getters.The current research status of VIPs is summarised,including their thermal conductivity,service life,and thermal bridging effects,as well as their applications in the field of architecture.This review aims to provide a comprehensive understanding for relevant practitioners on the factors influencing the thermal conductivity of VIPs,and based on which,measures can be taken to produce VIPs with lower thermal conductivity and longer service life.展开更多
Background:Diagnostic panels based on multiple biomarkers and clinical characteristics are considered more favorable than individual biomarker to diagnose hepatocellular carcinoma(HCC).Based on age,sex,alpha-fetoprote...Background:Diagnostic panels based on multiple biomarkers and clinical characteristics are considered more favorable than individual biomarker to diagnose hepatocellular carcinoma(HCC).Based on age,sex,alpha-fetoprotein(AFP),and protein induced by vitamin K absence II(PIVKA-II)with/without AFP-L3,ASAP and GALAD models are potential diagnostic panels.The diagnostic performances of these two panels were compared relative to HCC detection among patients with various etiologies of chronic liver diseases(CLDs).Methods:A multicenter case-control study recruited CLDs patients with and without HCC from 14 Chi-nese hospitals.The etiologies of CLDs included hepatitis B virus(HBV),hepatitis C virus(HCV),alcoholic liver disease(ALD),and nonalcoholic fatty liver disease(NAFLD).Using area under the receiver operating characteristic curve(AUC)values,the diagnostic performances of ASAP and GALAD models were com-pared to detect HCC among patients with various etiologies of CLDs.Results:Among 248 HCC patients and 722 CLD controls,the ASAP model demonstrated the highest AUC(0.886)to detect HCC at any stage,outperforming the GALAD model(0.853,P=0.001),as well as any individual biomarker(0.687-0.799,all P<0.001).In the subgroup analysis of various CLDs etiologies,the ASAP model outperformed the GALAD model to HCC independent of CLDs etiology.In addition,the ASAP model performed better in detecting early-stage(BCLC stage 0/A)HCC versus the GALAD model.Conclusions:Despite using one less laboratory variable(AFP-L3),the ASAP model demonstrated better diagnostic performance than the GALAD model to detect all-stage HCC among patients with various eti-ologies of CLDs-related HCC.展开更多
When the upper chord beam of the beam-string structure(BSS)is made of concrete-filled steel tube(CFST),its overall stiffness will change greatly with the construction of concrete placement,which will have an impact on...When the upper chord beam of the beam-string structure(BSS)is made of concrete-filled steel tube(CFST),its overall stiffness will change greatly with the construction of concrete placement,which will have an impact on the design of the tensioning plans and selection of control measures for the BSS.In order to accurately obtain the bending stiffness of CFST beam and clarify its impact on the mechanical properties of composite BSS during construction,the influence of some factors such as height-width ratio,wall thickness of steel tube,elasticity modulus of concrete,and friction coefficient on the bending stiffness are analyzed parametrically by the numerical simulation technology based on an actual project.The calculation formula of the equivalent bending stiffness of CFST is also established through mathematical statistical simulation.Then,the equivalent bending stiffness is introduced into the construction and use stages of the composite BSS,respectively,and the mechanical properties such as prestress-tensioning control value,structural deformation,and internal force of key members are comparatively analyzed when adopting two different construction plans.Moreover,the optimal construction plan of concrete placement first and then prestress-tensioning is proposed.展开更多
Under the“dual carbon”goal,local governments in China have strategically focused on enhancing capital utilization efficiency and enforcing environmental regulations to improve carbon emission performance.This dual a...Under the“dual carbon”goal,local governments in China have strategically focused on enhancing capital utilization efficiency and enforcing environmental regulations to improve carbon emission performance.This dual approach targets the intertwined challenges of economic development and environmental protection.Utilizing data from 266 prefecture-level cities in China from 2007 to 2019,this study systematically investigates the effects of capital matching and environmental regulation on carbon emission performance through the spatial Durbin model and the instrumental variable method.The results indicate that both capital matching and environmental regulation significantly enhance carbon emission performance.Capital matching demonstrates positive spatial spillover effects,whereas environmental regulation exhibits negative spatial spillover effects.Furthermore,there are synergistic effects between capital matching and environmental regulation that jointly enhance carbon emission performance.To address potential biases caused by endogenous environmental regulation,the study uses the proportion of environment-related words in provincial government work reports as an instrumental variable for environmental regulation.Additionally,to capture the heterogeneity in the environmental governance willingness and intensity of prefecture-level municipal governments,the study constructs heterogeneous instrumental variables.These variables are derived by multiplying the proportion of a prefecture-level city’s total industrial output value to the province’s total industrial output value with the proportion of environment-related words in the provincial government work reports.Analyses based on these instrumental variables reveal that endogenous issues in environmental regulation lead to an overestimation of its positive impact on carbon emission performance.展开更多
In a village in Shanxi,solar electricity is feeding into the grid thanks to an innovative technique In Nanzhanghe Village,located in Zhangzi District,Changzhi,Shanxi Province,rows of brand-new solar panels glisten und...In a village in Shanxi,solar electricity is feeding into the grid thanks to an innovative technique In Nanzhanghe Village,located in Zhangzi District,Changzhi,Shanxi Province,rows of brand-new solar panels glisten under the sun.The electricity they produce is collected by a new network,then steadily injected into a 10 kV power line after the volt-age is increased.展开更多
The primary objective of this study is to develop an innovative theoretical model to accurately predict the thermophysicalproperties of hybrid nanofluids designed to enhance cooling in solar panel applications.This re...The primary objective of this study is to develop an innovative theoretical model to accurately predict the thermophysicalproperties of hybrid nanofluids designed to enhance cooling in solar panel applications.This researchlays the groundwork for our future studies,which will focus on photovoltaic thermal applications.These nanofluidsconsist of water and nanoparticles of alumina(Al_(2)O_(3)),titanium dioxide(TiO_(2)),and copper(Cu),exploringvolumetric concentrations ranging from 0%to 4%for each type of nanoparticle,and up to 10%for total mixtures.The developed model accounts for complex interactions between the nanoparticles and the base fluid,as well assynergistic effects resulting from the coexistence of different nanoparticles.Detailed simulations have shownexceptional agreement with experimental results,reinforcing the credibility of our approach in accurately capturingthe thermophysical behavior of these hybrid nanofluids.Based on these results,our study proposes significantadvancements in the design and optimization of nanofluids for cooling applications in solar panels.These developmentsare crucial for improving the efficiency of solar installations by mitigating overheating effects,providinga solid foundation for practical applications in this rapidly evolving field.展开更多
Background:Patients with cancer are confronted not only with physical changes and pain but also with significant psychological challenges,including distress,anxiety,and depression,as a consequence of their diagnosis a...Background:Patients with cancer are confronted not only with physical changes and pain but also with significant psychological challenges,including distress,anxiety,and depression,as a consequence of their diagnosis and treatment.This study aimed to identify the factors influencing anxiety or depression in patientswith cancer,examine the relationship between the duration since cancer diagnosis and psychological state,and explore the association between these factors and the use of Korean medicine(KM).Methods:This study utilized data from the 2018 Korea Health Panel spanning 2008 to 2018.The analysis focused on adult participants(aged 19 and above)diagnosed with cancer who responded to their psychological state(i.e.,anxiety or depression)and the duration since their cancer diagnosis.The dependent variables were the presence of anxiety or depression and the utilization of KM.Descriptive statistics and multiple logistic regression analysis were used to investigate factors influencing these variables.Results:A total of 773 participants were included in the final analysis,of whom 214 reported prior KM experience.Multiple logistic regression analysis indicated that the likelihood of experiencing anxiety or depression decreased as the duration since cancer diagnosis increased.Factors associated with anxiety or depression in patients with cancer included sex(odds ratio[OR]=2.06),number of chronic diseases(OR=1.17),Charlson Comorbidity Index score(CCI score of 2:OR=1.60),and EQ-5D(EuroQol Five Dimensions Questionnaire)index(OR<0.001).Cancer patients without anxiety or depression were more likely to use KM if they had been diagnosed within three years,were female(OR=2.11),and had a higher number of chronic conditions(OR=1.20).In contrast,patients with anxiety or depression were more likely to utilizeKMif theyhadbeendiagnosed formore thanfive years(OR=6.30)and resided in urban areas.Conclusions:The results suggest that patterns of KM utilization among patients with cancer are associated with their psychological state.Future research should focus on identifying direct correlations between psychological factors and KM use in patients with cancer.展开更多
To address the limitations of traditional finite element methods,particularly the continuum assumption and difficulties in tracking the solid-liquid interface,this study introduces a lattice Boltzmann-based mathematic...To address the limitations of traditional finite element methods,particularly the continuum assumption and difficulties in tracking the solid-liquid interface,this study introduces a lattice Boltzmann-based mathematical and physical model to simulate flow and heat transfer in the laser welding molten pool of tin-coated copper used in solar panel busbars(a thin strip or wire of conductive metal embedded on the surface of a solar cell to collect and conduct the electricity generated by the photovoltaic cell).The model incorporates key external forces,including surface tension,solid-liquid interface tension,and recoil pressure.A moving and rotating Gaussian-body heat source is adopted,with temperature treated as an implicit function of enthalpy.Coupled iterative schemes for the temperature and velocity fields are constructed using a dual-distribution function approach with a D3Q15 lattice structure.The model is implemented in Python,utilizing libraries such as NumPy,SciPy,Mayavi,and Matplotlib for computation and visualization.Simulation results reveal that the heat transfer mechanism in the molten pool transitions from pure conduction to conduction-convection due to surface tension effects,leading to the formation of multiple counter-rotating vortex structures.The peak temperature at the pool center reaches 3200 K,with maximum melt depth and width measured at 0.5 and 1.2 mm,respectively.Over time,both penetration depth and melt width increase,though the width exhibits a more pronounced growth.Comparison with experimental thermal cycling data from laser weld joints shows strong agreement,with a maximum error of less than 1%,validating the accuracy of the proposed method.展开更多
This study introduces a novel approach for coupled aeroelastic analysis of panel subjected to supersonic airflow,utilizing Add-On Acoustic Black Hole(AABH)to mitigate panel flutter.Employing Galerkin's method to d...This study introduces a novel approach for coupled aeroelastic analysis of panel subjected to supersonic airflow,utilizing Add-On Acoustic Black Hole(AABH)to mitigate panel flutter.Employing Galerkin's method to discretize aeroelastic equation of panel and leveraging finite element method to derive a reduced discrete model of AABH,this study effectively couples two substructures via interface displacement.Investigation into the interactive force highlights the modal effective mass,frequency discrepancy between oscillation and AABH mode,and modal damping ratio as critical factors influencing individual AABH mode in flutter suppression.The selection of effective AABH modes,closely linked to these factors,directly influences the accuracy of simulations.The results reveal that AABH notably enhances the panel's critical flutter boundary by14.6%,a significant improvement over the 3.6%increase afforded by equivalent mass.Furthermore,AABH outperforms both the tuned mass damper and nonlinear energy sink in flutter suppression efficacy.By adjusting the AABH's geometrical parameters to increase the accumulative modal effective mass within the pertinent frequency range,or choosing a suitable installation position for AABH,its performance in flutter suppression is further optimized.These findings not only underscore the AABH's potential in enhancing aeroelastic stability but also provide a foundation for its optimal design.展开更多
Wind tunnel experiment and CFD(computational fluid dynamics)simulation with LES(large eddy simulation)have been conducted to investigate the characteristics of peak wind force coefficients of porous panels mounted on ...Wind tunnel experiment and CFD(computational fluid dynamics)simulation with LES(large eddy simulation)have been conducted to investigate the characteristics of peak wind force coefficients of porous panels mounted on the roofs of high-rise buildings.First,aerodynamic modelling of porous panels was discussed.The relation between pressure loss coefficient and porosity was obtained.Then,a wind tunnel experiment was conducted to measure the wind forces(net wind pressures)acting on solid and porous panels mounted on the roof of a high-rise building.Because it was difficult to measure the pressures on both sides of thin,porous panel at the same location simultaneously,we proposed to use the roof edge pressures near the panel for the panel’s inside-surface pressures.This experimental method was validated by a CFD simulation reproducing the wind tunnel experiment.The characteristics of peak wind force coefficients of porous panels mounted on the roofs of high-rise buildings were made clear.Finally,positive and negative peak wind force coefficients for designing the rooftop porous panels were proposed.展开更多
The increasing demand to decrease manufacturing costs and weight reduction is driving the aircraft industry to change the use of conventional riveted stiffened panels to integral stiffened panels(ISP)for aircraft fuse...The increasing demand to decrease manufacturing costs and weight reduction is driving the aircraft industry to change the use of conventional riveted stiffened panels to integral stiffened panels(ISP)for aircraft fuselage structures.ISP is a relatively new structure in aircraft industries and is considered the most significant development in a decade.These structures have the potential to replace the conventional stiffened panel due to the emergence of manufacturing technology,including welding,high-speed machining(HSM),extruding,and bonding.Although laser beam welding(LBW)and friction stir welding(FSW)have been applied in aircraft companies,many investigations into ISP continue to be conducted.In this review article,the current state of understanding and advancement of ISP structure is addressed.A particular explanation has been given to(a)buckling performance,(b)fatigue performance of the ISP,(c)modeling and simulation aspects,and(d)the impact of manufacturing decisions in welding processes on the final structural behavior of the ISP during service.Compared to riveted panels,machined ISP had a better compressive buckling load,and FSW integral panels had a lower buckling load than riveted panels.Compressive residual stress decreased the stress intensity factor(SIF)rates,slowing down the growth of fatigue cracks as occurred in FSW and LBW ISP.展开更多
The 2025 CIC Blue Ocean Forum for Worldwide Scientists,sponsored by the China Institute of Communications and organized by China Communications Editorial Office,will be held at the beginning of August this year,aiming...The 2025 CIC Blue Ocean Forum for Worldwide Scientists,sponsored by the China Institute of Communications and organized by China Communications Editorial Office,will be held at the beginning of August this year,aiming at the theme on“Sharing Academic Ideas&Promoting Innovation for Development”.The forum will feature world-class speakers,academic panels,and discussions.The Forum co-chairs invite the submission of original papers for presentation.展开更多
This study conducts a thorough examination of honeycomb sandwich panels with a lattice core,adopting advanced computational techniques for their modeling.The research extends its analysis to investigate the natural fr...This study conducts a thorough examination of honeycomb sandwich panels with a lattice core,adopting advanced computational techniques for their modeling.The research extends its analysis to investigate the natural frequency behavior of sandwich panels,encompassing the comprehensive assessment of the entire panel structure.At its core,the research applies the Representative Volume Element(RVE)theory to establish the equivalent material properties,thereby enhancing the predictive capabilities of lattice structure simulations.Themethodology applies these properties in the core of infinite panels,which are modeled using double periodic boundary conditions to explore their natural frequencies.Expanding beyond mere material characterization,the study introduces a novel approach to defining the material within the panel cores.By incorporating alternate materials such as steel and AlSiC,and by strategically modifying their ratios,the research streamlines the process of material variation without resorting to repetitive 3D operations on the constituent cells.This optimizes not only the computational resources but also offers insights into the structural response under diverse material compositions.Furthermore,the investigation extends its scope to analyze the influence of curvature on the structural behavior of lattice structures.Panels are modeled with varying degrees of curvature,ranging from single to double curvatures,including cylindrical and spherical configurations,across a spectrum of radii.A rigorous analysis is performed to study the effect of curvature on the mechanical performance and stability of lattice structures,offering valuable insights for design optimization and structural engineering applications.By building upon the existing knowledge and introducing innovative methodologies,this study contributes to improving the understanding of lattice structures and their applicability in diverse engineering contexts.展开更多
The 2025 CIC Blue Ocean Forum for Worldwide Scientists,sponsored by the China Institute of Communications and organized by China Communications Editorial Office,will be held at the beginning of August this year,aiming...The 2025 CIC Blue Ocean Forum for Worldwide Scientists,sponsored by the China Institute of Communications and organized by China Communications Editorial Office,will be held at the beginning of August this year,aiming at the theme on“Sharing Academic Ideas&Promoting Innovation for Development”.The forum will feature world-class speakers,academic panels,and discussions.The Forum co-chairs invite the submission of original papers for presentation.展开更多
Photovoltaic(PV)power forecasting is essential for balancing energy supply and demand in renewable energy systems.However,the performance of PV panels varies across different technologies due to differences in efficie...Photovoltaic(PV)power forecasting is essential for balancing energy supply and demand in renewable energy systems.However,the performance of PV panels varies across different technologies due to differences in efficiency and how they process solar radiation.This study evaluates the effectiveness of deep learning models in predicting PV power generation for three panel technologies:Hybrid-Si,Mono-Si,and Poly-Si,across three forecasting horizons:1-step,12-step,and 24-step.Among the tested models,the Convolutional Neural Network—Long Short-Term Memory(CNN-LSTM)architecture exhibited superior performance,particularly for the 24-step horizon,achieving R^(2)=0.9793 and MAE 0.0162 for the Poly-Si array,followed by Mono-Si(R^(2)=0.9768)and Hybrid-Si arrays(R^(2)=0.9769).These findings demonstrate that the CNN-LSTM model can provide accurate and reliable PV power predictions for all studied technologies.By identifying the most suitable predictive model for each panel technology,this study contributes to optimizing PV power forecasting and improving energy management strategies.展开更多
To enhance the resistance of honeycomb sandwich panel against local impact,this study delved into the matching relationship between face sheets and core.An integrated approach,combining experiment,simulation,and theor...To enhance the resistance of honeycomb sandwich panel against local impact,this study delved into the matching relationship between face sheets and core.An integrated approach,combining experiment,simulation,and theoretical methods,was used.Local loading experiments were conducted to validate the accuracy of the finite element model.Furthermore,a control equation was formulated to correlate structural parameters with response modes,and a matching coefficientλ(representing the ratio of core thickness to face sheet thickness)was introduced to establish a link between these parameters and impact characteristics.A demand-driven reverse design methodology for structural parameters was developed,with numerical simulations employed to assess its effectiveness.The results indicate that the proposed theory can accurately predict response modes and key indicators.An increase in theλbolsters the structural indentation resistance while concurrently heightens the likelihood of penetration.Conversely,a decrease in theλimproves the resistance to penetration,albeit potentially leading to significant deformations in the rear face sheet.Numerical simulations demonstrate that the reverse design methodology significantly enhances the structural penetration resistance.Comparative analyses indicate that appropriate matching reduces indentation depth by 27.4% and indentation radius by 41.8%of the proposed structure.展开更多
Microperforated panels(MPP)are widely used in noise control applications due to their excellent sound absorption performance.However,traditional single-layer MPPs suffer from a narrow sound absorption bandwidth,making...Microperforated panels(MPP)are widely used in noise control applications due to their excellent sound absorption performance.However,traditional single-layer MPPs suffer from a narrow sound absorption bandwidth,making it difficult to meet the demands for broadband sound absorption.To address this limitation,this study proposes a design approach for double-layer MPPs optimized using a genetic algorithm(GA).By optimizing structural parameters such as perforation diameter,panel thickness,perforation ratio,and cavity depth,the sound absorption performance of the double-layer MPP is significantly enhanced.The results demonstrate that the optimized double-layer MPP achieves an average sound absorption coefficient of 0.71 across the 100-5000 Hz frequency range,with a peak absorption coefficient exceeding 0.8 at 500 Hz,outperforming conventional sound-absorbing products of the same category.展开更多
The 2025 CIC Blue Ocean Forum for Worldwide Scientists,sponsored by the China Institute of Communications and organized by China Communications Editorial Office,will be held at the beginning of August this year,aiming...The 2025 CIC Blue Ocean Forum for Worldwide Scientists,sponsored by the China Institute of Communications and organized by China Communications Editorial Office,will be held at the beginning of August this year,aiming at the theme on“Sharing Academic Ideas&Promoting Innovation for Development”.The forum will feature world-class speakers,academic panels,and discussions.The Forum co-chairs invite the submission of original papers for presentation.展开更多
文摘This paper discusses the performance of a proposed panelized brick veneer over steel stud backup wall system and seismic isolation connections under lateral loads. The panelized wall system was developed to address some shortcomings of the conventional brick veneer wall type. The details of the system are briefly introduced. The study evaluated the performance of the system under out-of-plane simulated wind loads and in-plane cyclic loads using full-scale laboratory experiments. The test setup, test specimen, test procedure, and test results are presented and the performance of the system is evaluated accordingly.
文摘In recent years,there has been a growing global demand for carbon neutrality and energy efficiency,which are expected to become long-term trends.In the field of architecture,an effective approach to achieve this is to reduce heat loss in buildings.Vacuum insulation panels(VIPs),a type of high-performance insulation material,have been increasingly utilised in the construction industry and have played an increa-singly important role as their performance and manufacturing processes continue to improve.This paper provides a review of the factors affecting the thermal conductivity of VIPs and presents a detailed overview of the research progress on core materials,barrier films,and getters.The current research status of VIPs is summarised,including their thermal conductivity,service life,and thermal bridging effects,as well as their applications in the field of architecture.This review aims to provide a comprehensive understanding for relevant practitioners on the factors influencing the thermal conductivity of VIPs,and based on which,measures can be taken to produce VIPs with lower thermal conductivity and longer service life.
基金supported by grants from the National Natural Science Foundation of China(81972726 and 82273074)Abbott Diagnostics(ADD-China-2016).
文摘Background:Diagnostic panels based on multiple biomarkers and clinical characteristics are considered more favorable than individual biomarker to diagnose hepatocellular carcinoma(HCC).Based on age,sex,alpha-fetoprotein(AFP),and protein induced by vitamin K absence II(PIVKA-II)with/without AFP-L3,ASAP and GALAD models are potential diagnostic panels.The diagnostic performances of these two panels were compared relative to HCC detection among patients with various etiologies of chronic liver diseases(CLDs).Methods:A multicenter case-control study recruited CLDs patients with and without HCC from 14 Chi-nese hospitals.The etiologies of CLDs included hepatitis B virus(HBV),hepatitis C virus(HCV),alcoholic liver disease(ALD),and nonalcoholic fatty liver disease(NAFLD).Using area under the receiver operating characteristic curve(AUC)values,the diagnostic performances of ASAP and GALAD models were com-pared to detect HCC among patients with various etiologies of CLDs.Results:Among 248 HCC patients and 722 CLD controls,the ASAP model demonstrated the highest AUC(0.886)to detect HCC at any stage,outperforming the GALAD model(0.853,P=0.001),as well as any individual biomarker(0.687-0.799,all P<0.001).In the subgroup analysis of various CLDs etiologies,the ASAP model outperformed the GALAD model to HCC independent of CLDs etiology.In addition,the ASAP model performed better in detecting early-stage(BCLC stage 0/A)HCC versus the GALAD model.Conclusions:Despite using one less laboratory variable(AFP-L3),the ASAP model demonstrated better diagnostic performance than the GALAD model to detect all-stage HCC among patients with various eti-ologies of CLDs-related HCC.
文摘When the upper chord beam of the beam-string structure(BSS)is made of concrete-filled steel tube(CFST),its overall stiffness will change greatly with the construction of concrete placement,which will have an impact on the design of the tensioning plans and selection of control measures for the BSS.In order to accurately obtain the bending stiffness of CFST beam and clarify its impact on the mechanical properties of composite BSS during construction,the influence of some factors such as height-width ratio,wall thickness of steel tube,elasticity modulus of concrete,and friction coefficient on the bending stiffness are analyzed parametrically by the numerical simulation technology based on an actual project.The calculation formula of the equivalent bending stiffness of CFST is also established through mathematical statistical simulation.Then,the equivalent bending stiffness is introduced into the construction and use stages of the composite BSS,respectively,and the mechanical properties such as prestress-tensioning control value,structural deformation,and internal force of key members are comparatively analyzed when adopting two different construction plans.Moreover,the optimal construction plan of concrete placement first and then prestress-tensioning is proposed.
文摘Under the“dual carbon”goal,local governments in China have strategically focused on enhancing capital utilization efficiency and enforcing environmental regulations to improve carbon emission performance.This dual approach targets the intertwined challenges of economic development and environmental protection.Utilizing data from 266 prefecture-level cities in China from 2007 to 2019,this study systematically investigates the effects of capital matching and environmental regulation on carbon emission performance through the spatial Durbin model and the instrumental variable method.The results indicate that both capital matching and environmental regulation significantly enhance carbon emission performance.Capital matching demonstrates positive spatial spillover effects,whereas environmental regulation exhibits negative spatial spillover effects.Furthermore,there are synergistic effects between capital matching and environmental regulation that jointly enhance carbon emission performance.To address potential biases caused by endogenous environmental regulation,the study uses the proportion of environment-related words in provincial government work reports as an instrumental variable for environmental regulation.Additionally,to capture the heterogeneity in the environmental governance willingness and intensity of prefecture-level municipal governments,the study constructs heterogeneous instrumental variables.These variables are derived by multiplying the proportion of a prefecture-level city’s total industrial output value to the province’s total industrial output value with the proportion of environment-related words in the provincial government work reports.Analyses based on these instrumental variables reveal that endogenous issues in environmental regulation lead to an overestimation of its positive impact on carbon emission performance.
文摘In a village in Shanxi,solar electricity is feeding into the grid thanks to an innovative technique In Nanzhanghe Village,located in Zhangzi District,Changzhi,Shanxi Province,rows of brand-new solar panels glisten under the sun.The electricity they produce is collected by a new network,then steadily injected into a 10 kV power line after the volt-age is increased.
文摘The primary objective of this study is to develop an innovative theoretical model to accurately predict the thermophysicalproperties of hybrid nanofluids designed to enhance cooling in solar panel applications.This researchlays the groundwork for our future studies,which will focus on photovoltaic thermal applications.These nanofluidsconsist of water and nanoparticles of alumina(Al_(2)O_(3)),titanium dioxide(TiO_(2)),and copper(Cu),exploringvolumetric concentrations ranging from 0%to 4%for each type of nanoparticle,and up to 10%for total mixtures.The developed model accounts for complex interactions between the nanoparticles and the base fluid,as well assynergistic effects resulting from the coexistence of different nanoparticles.Detailed simulations have shownexceptional agreement with experimental results,reinforcing the credibility of our approach in accurately capturingthe thermophysical behavior of these hybrid nanofluids.Based on these results,our study proposes significantadvancements in the design and optimization of nanofluids for cooling applications in solar panels.These developmentsare crucial for improving the efficiency of solar installations by mitigating overheating effects,providinga solid foundation for practical applications in this rapidly evolving field.
基金supported by a grant of the R&D Project through the Korea Health Industry Development Institute(KHIDI),funded by the Ministry of Health&Welfare,Republic of Korea(grant number:RS-2023-KH139376).
文摘Background:Patients with cancer are confronted not only with physical changes and pain but also with significant psychological challenges,including distress,anxiety,and depression,as a consequence of their diagnosis and treatment.This study aimed to identify the factors influencing anxiety or depression in patientswith cancer,examine the relationship between the duration since cancer diagnosis and psychological state,and explore the association between these factors and the use of Korean medicine(KM).Methods:This study utilized data from the 2018 Korea Health Panel spanning 2008 to 2018.The analysis focused on adult participants(aged 19 and above)diagnosed with cancer who responded to their psychological state(i.e.,anxiety or depression)and the duration since their cancer diagnosis.The dependent variables were the presence of anxiety or depression and the utilization of KM.Descriptive statistics and multiple logistic regression analysis were used to investigate factors influencing these variables.Results:A total of 773 participants were included in the final analysis,of whom 214 reported prior KM experience.Multiple logistic regression analysis indicated that the likelihood of experiencing anxiety or depression decreased as the duration since cancer diagnosis increased.Factors associated with anxiety or depression in patients with cancer included sex(odds ratio[OR]=2.06),number of chronic diseases(OR=1.17),Charlson Comorbidity Index score(CCI score of 2:OR=1.60),and EQ-5D(EuroQol Five Dimensions Questionnaire)index(OR<0.001).Cancer patients without anxiety or depression were more likely to use KM if they had been diagnosed within three years,were female(OR=2.11),and had a higher number of chronic conditions(OR=1.20).In contrast,patients with anxiety or depression were more likely to utilizeKMif theyhadbeendiagnosed formore thanfive years(OR=6.30)and resided in urban areas.Conclusions:The results suggest that patterns of KM utilization among patients with cancer are associated with their psychological state.Future research should focus on identifying direct correlations between psychological factors and KM use in patients with cancer.
基金Science and Technology Research Key Competitive Project of Quzhou Science and Technology Bureau(Nos.2023K266,2024K010)General Project for Cultivating Outstanding Young Teachers in Anhui Province’s Universities(2025).
文摘To address the limitations of traditional finite element methods,particularly the continuum assumption and difficulties in tracking the solid-liquid interface,this study introduces a lattice Boltzmann-based mathematical and physical model to simulate flow and heat transfer in the laser welding molten pool of tin-coated copper used in solar panel busbars(a thin strip or wire of conductive metal embedded on the surface of a solar cell to collect and conduct the electricity generated by the photovoltaic cell).The model incorporates key external forces,including surface tension,solid-liquid interface tension,and recoil pressure.A moving and rotating Gaussian-body heat source is adopted,with temperature treated as an implicit function of enthalpy.Coupled iterative schemes for the temperature and velocity fields are constructed using a dual-distribution function approach with a D3Q15 lattice structure.The model is implemented in Python,utilizing libraries such as NumPy,SciPy,Mayavi,and Matplotlib for computation and visualization.Simulation results reveal that the heat transfer mechanism in the molten pool transitions from pure conduction to conduction-convection due to surface tension effects,leading to the formation of multiple counter-rotating vortex structures.The peak temperature at the pool center reaches 3200 K,with maximum melt depth and width measured at 0.5 and 1.2 mm,respectively.Over time,both penetration depth and melt width increase,though the width exhibits a more pronounced growth.Comparison with experimental thermal cycling data from laser weld joints shows strong agreement,with a maximum error of less than 1%,validating the accuracy of the proposed method.
基金the National Key Research and Development Program of China(No.2021YFB3400100)the National Natural Science Foundation of China(Nos.52235003&U2241261)。
文摘This study introduces a novel approach for coupled aeroelastic analysis of panel subjected to supersonic airflow,utilizing Add-On Acoustic Black Hole(AABH)to mitigate panel flutter.Employing Galerkin's method to discretize aeroelastic equation of panel and leveraging finite element method to derive a reduced discrete model of AABH,this study effectively couples two substructures via interface displacement.Investigation into the interactive force highlights the modal effective mass,frequency discrepancy between oscillation and AABH mode,and modal damping ratio as critical factors influencing individual AABH mode in flutter suppression.The selection of effective AABH modes,closely linked to these factors,directly influences the accuracy of simulations.The results reveal that AABH notably enhances the panel's critical flutter boundary by14.6%,a significant improvement over the 3.6%increase afforded by equivalent mass.Furthermore,AABH outperforms both the tuned mass damper and nonlinear energy sink in flutter suppression efficacy.By adjusting the AABH's geometrical parameters to increase the accumulative modal effective mass within the pertinent frequency range,or choosing a suitable installation position for AABH,its performance in flutter suppression is further optimized.These findings not only underscore the AABH's potential in enhancing aeroelastic stability but also provide a foundation for its optimal design.
文摘Wind tunnel experiment and CFD(computational fluid dynamics)simulation with LES(large eddy simulation)have been conducted to investigate the characteristics of peak wind force coefficients of porous panels mounted on the roofs of high-rise buildings.First,aerodynamic modelling of porous panels was discussed.The relation between pressure loss coefficient and porosity was obtained.Then,a wind tunnel experiment was conducted to measure the wind forces(net wind pressures)acting on solid and porous panels mounted on the roof of a high-rise building.Because it was difficult to measure the pressures on both sides of thin,porous panel at the same location simultaneously,we proposed to use the roof edge pressures near the panel for the panel’s inside-surface pressures.This experimental method was validated by a CFD simulation reproducing the wind tunnel experiment.The characteristics of peak wind force coefficients of porous panels mounted on the roofs of high-rise buildings were made clear.Finally,positive and negative peak wind force coefficients for designing the rooftop porous panels were proposed.
基金The authors express their gratitude to Universiti Pura Malaysia(UPM),Malaysia for granting Putra IPS vote number 9742900.
文摘The increasing demand to decrease manufacturing costs and weight reduction is driving the aircraft industry to change the use of conventional riveted stiffened panels to integral stiffened panels(ISP)for aircraft fuselage structures.ISP is a relatively new structure in aircraft industries and is considered the most significant development in a decade.These structures have the potential to replace the conventional stiffened panel due to the emergence of manufacturing technology,including welding,high-speed machining(HSM),extruding,and bonding.Although laser beam welding(LBW)and friction stir welding(FSW)have been applied in aircraft companies,many investigations into ISP continue to be conducted.In this review article,the current state of understanding and advancement of ISP structure is addressed.A particular explanation has been given to(a)buckling performance,(b)fatigue performance of the ISP,(c)modeling and simulation aspects,and(d)the impact of manufacturing decisions in welding processes on the final structural behavior of the ISP during service.Compared to riveted panels,machined ISP had a better compressive buckling load,and FSW integral panels had a lower buckling load than riveted panels.Compressive residual stress decreased the stress intensity factor(SIF)rates,slowing down the growth of fatigue cracks as occurred in FSW and LBW ISP.
文摘The 2025 CIC Blue Ocean Forum for Worldwide Scientists,sponsored by the China Institute of Communications and organized by China Communications Editorial Office,will be held at the beginning of August this year,aiming at the theme on“Sharing Academic Ideas&Promoting Innovation for Development”.The forum will feature world-class speakers,academic panels,and discussions.The Forum co-chairs invite the submission of original papers for presentation.
文摘This study conducts a thorough examination of honeycomb sandwich panels with a lattice core,adopting advanced computational techniques for their modeling.The research extends its analysis to investigate the natural frequency behavior of sandwich panels,encompassing the comprehensive assessment of the entire panel structure.At its core,the research applies the Representative Volume Element(RVE)theory to establish the equivalent material properties,thereby enhancing the predictive capabilities of lattice structure simulations.Themethodology applies these properties in the core of infinite panels,which are modeled using double periodic boundary conditions to explore their natural frequencies.Expanding beyond mere material characterization,the study introduces a novel approach to defining the material within the panel cores.By incorporating alternate materials such as steel and AlSiC,and by strategically modifying their ratios,the research streamlines the process of material variation without resorting to repetitive 3D operations on the constituent cells.This optimizes not only the computational resources but also offers insights into the structural response under diverse material compositions.Furthermore,the investigation extends its scope to analyze the influence of curvature on the structural behavior of lattice structures.Panels are modeled with varying degrees of curvature,ranging from single to double curvatures,including cylindrical and spherical configurations,across a spectrum of radii.A rigorous analysis is performed to study the effect of curvature on the mechanical performance and stability of lattice structures,offering valuable insights for design optimization and structural engineering applications.By building upon the existing knowledge and introducing innovative methodologies,this study contributes to improving the understanding of lattice structures and their applicability in diverse engineering contexts.
文摘The 2025 CIC Blue Ocean Forum for Worldwide Scientists,sponsored by the China Institute of Communications and organized by China Communications Editorial Office,will be held at the beginning of August this year,aiming at the theme on“Sharing Academic Ideas&Promoting Innovation for Development”.The forum will feature world-class speakers,academic panels,and discussions.The Forum co-chairs invite the submission of original papers for presentation.
文摘Photovoltaic(PV)power forecasting is essential for balancing energy supply and demand in renewable energy systems.However,the performance of PV panels varies across different technologies due to differences in efficiency and how they process solar radiation.This study evaluates the effectiveness of deep learning models in predicting PV power generation for three panel technologies:Hybrid-Si,Mono-Si,and Poly-Si,across three forecasting horizons:1-step,12-step,and 24-step.Among the tested models,the Convolutional Neural Network—Long Short-Term Memory(CNN-LSTM)architecture exhibited superior performance,particularly for the 24-step horizon,achieving R^(2)=0.9793 and MAE 0.0162 for the Poly-Si array,followed by Mono-Si(R^(2)=0.9768)and Hybrid-Si arrays(R^(2)=0.9769).These findings demonstrate that the CNN-LSTM model can provide accurate and reliable PV power predictions for all studied technologies.By identifying the most suitable predictive model for each panel technology,this study contributes to optimizing PV power forecasting and improving energy management strategies.
基金Project(2022A02480004)supported by the Major Project of China Railway Design CorporationProject(2023RC1011)supported by the Science and Technology Innovation Program of Hunan Province,China+2 种基金Project(2024JJ6515)supported by the Hunan Provincial Natural Science Foundation,ChinaProject(kq2402220)supported by the Natural Science Foundation of Changsha City,ChinaProject(52402438)supported by the National Natural Science Foundation of China。
文摘To enhance the resistance of honeycomb sandwich panel against local impact,this study delved into the matching relationship between face sheets and core.An integrated approach,combining experiment,simulation,and theoretical methods,was used.Local loading experiments were conducted to validate the accuracy of the finite element model.Furthermore,a control equation was formulated to correlate structural parameters with response modes,and a matching coefficientλ(representing the ratio of core thickness to face sheet thickness)was introduced to establish a link between these parameters and impact characteristics.A demand-driven reverse design methodology for structural parameters was developed,with numerical simulations employed to assess its effectiveness.The results indicate that the proposed theory can accurately predict response modes and key indicators.An increase in theλbolsters the structural indentation resistance while concurrently heightens the likelihood of penetration.Conversely,a decrease in theλimproves the resistance to penetration,albeit potentially leading to significant deformations in the rear face sheet.Numerical simulations demonstrate that the reverse design methodology significantly enhances the structural penetration resistance.Comparative analyses indicate that appropriate matching reduces indentation depth by 27.4% and indentation radius by 41.8%of the proposed structure.
文摘Microperforated panels(MPP)are widely used in noise control applications due to their excellent sound absorption performance.However,traditional single-layer MPPs suffer from a narrow sound absorption bandwidth,making it difficult to meet the demands for broadband sound absorption.To address this limitation,this study proposes a design approach for double-layer MPPs optimized using a genetic algorithm(GA).By optimizing structural parameters such as perforation diameter,panel thickness,perforation ratio,and cavity depth,the sound absorption performance of the double-layer MPP is significantly enhanced.The results demonstrate that the optimized double-layer MPP achieves an average sound absorption coefficient of 0.71 across the 100-5000 Hz frequency range,with a peak absorption coefficient exceeding 0.8 at 500 Hz,outperforming conventional sound-absorbing products of the same category.
文摘The 2025 CIC Blue Ocean Forum for Worldwide Scientists,sponsored by the China Institute of Communications and organized by China Communications Editorial Office,will be held at the beginning of August this year,aiming at the theme on“Sharing Academic Ideas&Promoting Innovation for Development”.The forum will feature world-class speakers,academic panels,and discussions.The Forum co-chairs invite the submission of original papers for presentation.
