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
Characterized by the quasi-conically symmetric flow field,κshock wave system,and highly three-dimensional separation structures,the swept shock-wave/boundarylayer interaction(SBLI)induced by sharp fins is one of the ...Characterized by the quasi-conically symmetric flow field,κshock wave system,and highly three-dimensional separation structures,the swept shock-wave/boundarylayer interaction(SBLI)induced by sharp fins is one of the most important phenomena in supersonic flights.An aerothermoelastic analysis is conducted on the interactions between thin-walled panels and swept SBLIs.The results of rigid wall condition,aeroelastic analysis and aerothermoelastic analysis are compared to highlight the significant influence of fluid-thermal-structural interactions on the structure and the flow field of swept SBLIs.The results show that in the aeroelastic analysis,for the material applied to the panel,although a dynamic structural response is observed,the deformation is minor and has a limited influence on the flow field.However,in the aerothermoelastic analysis,the consideration of aerodynamic heating has a significant impact on the structural response and the flow field.The deformation is an order of magnitude larger than that in the aeroelastic analysis with high vibration frequency and various main frequencies at different locations.As a result,the flow field is no longer quasi-conically symmetric.Theλshock wave system and separation structures are completely disrupted by multiple shock and expansion waves induced by the large structural deformation and become much more complex with highly three-dimensional features.This research highlights the significance of investigations on complex three-dimensional aerothermoelastic problems for supersonic flight vehicles.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
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
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
Background:Adolescent depression and school refusal(SR)are prevalent and important global concerns that need to be understood and addressed.Cross-sectional associations have been reported but prospective relationships...Background:Adolescent depression and school refusal(SR)are prevalent and important global concerns that need to be understood and addressed.Cross-sectional associations have been reported but prospective relationships between them remain unclear.This longitudinal study investigated the bidirectional relationships between these two problems among Chinese adolescents.Methods:A longitudinal study was conducted in Taizhou,China,surveying students of three junior high schools,three senior high schools,and one vocational high school.A total of 3882 students completed the questionnaire at baseline(T1);3167 of them completed an identical follow-up questionnaire after 6 months(T2).Depression was assessed via the Patient Health Questionnaire(PHQ-9)and SR via the modified Chinese version of The School Refusal Assessment Scale-Revised(SRAS-R).Cross-lagged panel modeling(CLPM)analysis was conducted to test the reciprocal relationships,adjusting for socio-demographic factors.Multiple group analysis was conducted to test whether the CLPM differed by gender and grade.Results:Statistically significant bidirectional relationships were found.A higher level of SR assessed at T1 is prospectively associated with a higher level of depression at T2(β=0.07,p=0.006);a higher level of depression at T1 also is prospectively associated with a higher level of SR at T2(β=0.14,p<0.001).Such models differed significantly by neither gender nor grade.Conclusion:SR and depression should be seen as each other’s mutually reinforcing association.The bidirectional relationships potentially result in a vicious cycle.Early interventions may target both problems concurrently.Future studies may involve more time points and test some mediators.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
Cooling system design applicable to more than one photovoltaic(PV)unit may be challenging due to the arrangement and geometry of the modules.Different cooling techniques are provided in this study to regulate the temp...Cooling system design applicable to more than one photovoltaic(PV)unit may be challenging due to the arrangement and geometry of the modules.Different cooling techniques are provided in this study to regulate the temperature of conductive panels that are arranged perpendicular to each other.The model uses two vented cavity systems and one L-shaped channel with ternary nanofluid enhanced non-uniform magnetic field.Their cooling performances and comparative results between different systems are provided.The finite element method is used to conduct a numerical analysis for a range of values of the following:the strength of themagnetic field(Hartmann number(Ha)between 0 and 50),the inclination of the magnetic field(γbetween 0 and 90),and the loading of nanoparticles in the base fluid(ϕbetween 0 and 0.03),taking into account both uniformand non-uniformmagnetic fields.For the L-shaped channel and vented cavities,vortex size is controlled by imposing magnetic field and adjusting its strength.Whether uniform or non-uniform magnetic field is applied affects the cooling performances for different cooling configurations.Temperature drops of the horizontal panel with different magnetic field strengths by using channel cooling,vented cavity-1 and vented cavity-2 systems for uniformmagnetic are 11℃,21.5℃,and 3℃when the reference case of Ha=0 is considered for the same cooling systems.However,they become 9.5℃,13.5℃,and 12.5℃when nonuniform magnetic field is used.In the presence of uniform magnetic field effects and changing its magnitude,the use of cooling channel in vented cavity-1 and vented cavity-2 systems results in temperature drops of 4℃,10.8℃,and 3.8℃for vertical panels.On the other hand,when non-uniform magnetic field effects are present,they become 0.5℃,2.1℃,and 9℃.For L-channel cooling,the average Nu for the horizontal panel is more affected byγ,andNu rises asγrises.With increasing nanoparticle loading of ternary nanofluid,the average panel surface temperature shows a linear drop.For the horizontal panel,the temperature declines for nanofluid at the highest loading are 4℃,10℃,and 12℃as compared to using only base fluid.The values of 5℃,7℃,and 11℃are obtained for the vertical panel.Different cooling systems’performance is estimated using artificial neural networks.The method captures the combined impact of applying non-uniformmagnetic field and nanofluid together on the cooling performancewhile accounting for varied cooling strategies for both panels.展开更多
This study investigates the convergence hypothesis and stochastic dynamics of agricultural land use and ecological balance across 13 major agricultural countries from 1992 to 2022.The study's concentrated samples ...This study investigates the convergence hypothesis and stochastic dynamics of agricultural land use and ecological balance across 13 major agricultural countries from 1992 to 2022.The study's concentrated samples are Russia,the United States,the Netherlands,Brazil,Germany,China,France,Spain,Italy,Canada,Belgium,Indonesia,and India.The research uncovers notable variations in ecological balance by utilizing a comprehensive set of advanced panel unit root tests(Panel CIPS,CADF,Panel-LM,Panel-KPSS,and Bahmani-Oskooee et al.’s Panel KPSS Unit Root Test).The findings highlight significant improvements in Canada,contrasting with declines in the Netherlands,France,Germany,and the United States.The results indicate convergence in ecological balance among these countries,suggesting that agricultural practices are progressively aligning with sustainability objectives.The considered countries can determine and enact joint and collective policy actions addressing cropland sustainability.However,the univariate outcome also shows that the cropland ecological balance of Germany,China,France,Indonesia,and India does contain a unit root and stationary which means the presence of the constant-mean.The univariate actions from the mentioned governments will not promote persistent impact.Therefore,joint actions determined by the countries considered are recommended for the mentioned countries.However,the rest of the countries also enact local policies.The insights gained are critical for informing global sustainability strategies and aiding policymakers in developing effective measures to enhance agricultural practices and mitigate environmental impacts.This research provides a data-driven foundation for optimizing agricultural sustainability and supports international efforts to achieve long-term ecological stability.展开更多
Objective To study the causal relationship between R&D investment and enterprise performance of domestic pharmaceutical enterprises.Methods Panel data model was adopted for empirical analysis.Results and Conclusio...Objective To study the causal relationship between R&D investment and enterprise performance of domestic pharmaceutical enterprises.Methods Panel data model was adopted for empirical analysis.Results and Conclusion Increasing the R&D investment intensity of pharmaceutical enterprises in the Yangtze River Delta and Zhejiang by 1%will increase their profit margins by 0.79%and 0.46%.On the contrary,if the profit margin increases by 1%,the R&D investment intensity will increase by 0.25%and 0.19%.If the profit margin of pharmaceutical enterprises in Beijing,Tianjin,Hebei,Chengdu,Chongqing and other regions increases by 1%,the R&D investment intensity will increase by 0.14%,0.07%and 0.1%,respectively,which are lower than those in the Yangtze River Delta and Zhejiang.The relationship between R&D investment and enterprise performance of pharmaceutical enterprises in the Yangtze River Delta and Zhejiang Province is Granger causality,showing a two-way positive effect.Profits and R&D investment of pharmaceutical enterprises in Beijing,Tianjin,Hebei,Chengdu,Chongqing and other regions are also Granger causality.But in the Pearl River Delta,profits and R&D investment have not passed the stability test,it is impossible to determine the causality between them.展开更多
The buckling behavior of stiffened panels is significantly influenced by material and geometric defects,making it a critical factor in ensuring structural integrity and safety.These panels are widely used in mechanica...The buckling behavior of stiffened panels is significantly influenced by material and geometric defects,making it a critical factor in ensuring structural integrity and safety.These panels are widely used in mechanical,aerospace,marine,and civil engineering applications due to their ability to enhance bending stiffness with minimal additional weight.Under high loads or stress concentrations,localized structural failures can initiate global buckling in stiffened panels.This study investigates how such defects affect the critical buckling load,stiffness,and thickness of stiffened panels.Two finite element analyses were conducted:a linear analysis to identify the initial buckling mode and a nonlinear analysis using the Riks algorithm in Abaqus CAE,incorporating localized imperfections.The simulations show that material and geometric defects can reduce buckling resistance depending on their severity.展开更多
In 2019,China had over 13.14 million dementia cases,with incidence rates of(56.47–207.08)/100,000[1].Early cognitive impairment—a key dementia symptom—reduces quality of life,increases care dependence,and lowers su...In 2019,China had over 13.14 million dementia cases,with incidence rates of(56.47–207.08)/100,000[1].Early cognitive impairment—a key dementia symptom—reduces quality of life,increases care dependence,and lowers survival in older adults[2].A decline in physical function can also be observed in older adults with increasing age.Grip strength has been shown to be a marker of overall physiological function in older adults.展开更多
Objective:This study aimed to examine the influence of behavioral lifestyle factors on recent episodic memory retention capacity among young-old adults(aged 60-69 years)in China.The findings provide scientific evidenc...Objective:This study aimed to examine the influence of behavioral lifestyle factors on recent episodic memory retention capacity among young-old adults(aged 60-69 years)in China.The findings provide scientific evidence to inform proactive strategies to mitigate cognitive decline risk within China’s rapidly aging population.Methods:Utilizing data from the 2022 wave of the China Family Panel Studies(CFPS),a total of 2,772 adults aged 60-69 were included in the analytical sample.Recent episodic memory retention capacity(scored 0-5 points,based on self-reported assessment)served as the dependent variable.Six categories of behavioral lifestyle indicators(including exercise frequency,sleep quality,dietary patterns,etc.)were analyzed as independent variables.Associations were assessed using multivariate ordinal logistic regression models,controlling for relevant covariates.Results:Self-reported potential impairment in recent episodic memory was identified by 47.19%of respondents.Multivariate analysis revealed significant associations between behavioral lifestyle factors and memory retention capacity.Regular exercise(OR=1.297,95%CI:1.118-1.504),meat consumption(OR=1.765,95%CI:1.393-2.237),regular reading habits(OR=1.599,95%CI:1.283-1.992),and internet use(OR=1.413,95%CI:1.217-1.641)emerged as significant protective factors.Abnormal sleep duration was detrimentally associated with retention capacity(too short:OR=0.728,95%CI:0.591-0.897;too long:OR=0.810,95%CI:0.670-0.980).Significant associations were also observed for control variables:urban residence(OR=1.270,95%CI:1.100-1.467),high school education or above(OR=1.543,95%CI:1.293-1.841),and better self-rated health status(OR=1.156,95%CI:1.089-1.227)were positively correlated with better memory retention.Conclusions:Optimal sleep duration,regular physical exercise,meat intake,habitual reading,and internet engagement positively predict self-assessed recent episodic memory retention capacity in Chinese young-old adults.These findings underscore the potential for multi-faceted lifestyle interventions to enhance cog-nitive health in aging populations.Specifically,strategies should encompass community-based sleep hygiene management,tailored nutritional interventions(especially promoting adequate protein sources like meat),enhanced digital literacy and internet accessibility programs,and the promotion of age-appropriate physical activity initiatives.Furthermore,implementing culturally responsive strategies adapted to urban-rural contexts-such as deploying“mobile cognitive health units”in rural areas and fostering digital reading platforms in urban settings-is recommended to optimize intervention effectiveness.展开更多
Due to the continuous increase in global energy demand,photovoltaic solar energy generation and associated maintenance requirements have significantly expanded.One critical maintenance challenge in photovoltaic instal...Due to the continuous increase in global energy demand,photovoltaic solar energy generation and associated maintenance requirements have significantly expanded.One critical maintenance challenge in photovoltaic installations is detecting hot spots,localized overheating defects in solar cells that drastically reduce efficiency and can lead to permanent damage.Traditional methods for detecting these defects rely on manual inspections using thermal imaging,which are costly,labor-intensive,and impractical for large-scale installations.This research introduces an automated hybrid system based on two specialized convolutional neural networks deployed in a cascaded architecture.The first convolutional neural network efficiently detects and isolates individual solar panels from high-resolution aerial thermal images captured by drones.Subsequently,a second,more advanced convolutional neural network accurately classifies each isolated panel as either defective or healthy,effectively distinguishing genuine thermal anomalies from false positives caused by reflections or glare.Experimental validation on a real-world dataset comprising thousands of thermal images yielded exceptional accuracy,significantly reducing inspection time,costs,and the likelihood of false defect detections.This proposed system enhances the reliability and efficiency of photovoltaic plant inspections,thus contributing to improved operational performance and economic viability.展开更多
This study systematically examines the energy dissipation mechanisms and ballistic characteristics of foam sandwich panels(FSP)under high-velocity impact using the explicit non-linear finite element method.Based on th...This study systematically examines the energy dissipation mechanisms and ballistic characteristics of foam sandwich panels(FSP)under high-velocity impact using the explicit non-linear finite element method.Based on the geometric topology of the FSP system,three FSP configurations with the same areal density are derived,namely multi-layer,gradient core and asymmetric face sheet,and three key structural parameters are identified:core thickness(t_(c)),face sheet thickness(t_(f))and overlap face/core number(n_(o)).The ballistic performance of the FSP system is comprehensively evaluated in terms of the ballistic limit velocity(BLV),deformation modes,energy dissipation mechanism,and specific penetration energy(SPE).The results show that the FSP system exhibits a significant configuration dependence,whose ballistic performance ranking is:asymmetric face sheet>gradient core>multi-layer.The mass distribution of the top and bottom face sheets plays a critical role in the ballistic resistance of the FSP system.Both BLV and SPE increase with tf,while the raising tcor noleads to an increase in BLV but a decrease in SPE.Further,a face-core synchronous enhancement mechanism is discovered by the energy dissipation analysis,based on which the ballistic optimization procedure is also conducted and a design chart is established.This study shed light on the anti-penetration mechanism of the FSP system and might provide a theoretical basis for its engineering application.展开更多
Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in China.Safety control is essential to long-term operation of these dams.This study employed the flexibility coefficient and ...Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in China.Safety control is essential to long-term operation of these dams.This study employed the flexibility coefficient and plastic complementary energy norm to assess the structural safety of arch dams.A comprehensive analysis was conducted,focusing on differences among conventional methods in characterizing the structural behavior of the Xiaowan arch dam in China.Subsequently,the spatiotemporal characteristics of the measured performance of the Xiaowan dam were explored,including periodicity,convergence,and time-effect characteristics.These findings revealed the governing mechanism of main factors.Furthermore,a heterogeneous spatial panel vector model was developed,considering both common factors and specific factors affecting the safety and performance of arch dams.This model aims to comprehensively illustrate spatial heterogeneity between the entire structure and local regions,introducing a specific effect quantity to characterize local deformation differences.Ultimately,the proposed model was applied to the Xiaowan arch dam,accurately quantifying the spatiotemporal heterogeneity of dam performance.Additionally,the spatiotemporal distri-bution characteristics of environmental load effects on different parts of the dam were reasonably interpreted.Validation of the model prediction enhances its credibility,leading to the formulation of health diagnosis criteria for future long-term operation of the Xiaowan dam.The findings not only enhance the predictive ability and timely control of ultrahigh arch dams'performance but also provide a crucial basis for assessing the effectiveness of engineering treatment measures.展开更多
A large amount of genome-wide association study(GWAS)panels together with quantitative-trait locus(QTL)information associated with breeding-targeted traits have been described in wheat(Triticum aestivum L.).However,th...A large amount of genome-wide association study(GWAS)panels together with quantitative-trait locus(QTL)information associated with breeding-targeted traits have been described in wheat(Triticum aestivum L.).However,the application of mapping results from a GWAS panel to conventional wheat breeding remains a challenge.In this study,we first report a general genetic map which was constructed from 44 published linkage maps.It permits the estimation of genetic distances between any two genetic loci with physical map positions,thereby unifying the linkage relationships between QTL,genes,and genomic markers from multiple genetic populations.Second,we describe QTL mapping in a wheat GWAS panel of 688 accessions,identifying 77 QTL associated with 12 yield and grain-quality traits.Because these QTL have known physical map positions,they could be mapped onto the general map.Finally,we present a design approach to wheat breeding by using known QTL information and computer simulation.Potential crosses between parents in the GWAS panel may be evaluated by the relative frequency of the target genotype,trait correlations in simulated progeny populations,and genetic gain of selected progenies.It is possible to simultaneously improve yield and grain quality by suitable parental selection,progeny population size,and progeny selection scheme.Applying the design approach will allow identifying the most promising crosses and selection schemes in advance of the field experiment,increasing predictability and efficiency in wheat breeding.展开更多
The primary goal of this study is to fully grasp the production flow of the new processing technologies for manufacturing composite stiffened panels incorporating cost as one of the design variables early in the desig...The primary goal of this study is to fully grasp the production flow of the new processing technologies for manufacturing composite stiffened panels incorporating cost as one of the design variables early in the design process. An approach is presented to determine the optimum process for cost as objective function. A cost estimation model is established based on the integrally molding process. In the model,the cost drivers which are related to the manufacture processes in terms of material,labor,tool and equipment costs are taken into account. At the same time,estimation software combined computer is developed to aid optimization design. A case of manufacturing composite stiffened panels with T-shaped stiffeners is examined. Excellent agreement shows the optimum process for cost is obtained for the composite stiffened panel with cocuring. It is also revealed that the estimation software combined computer is efficient. The estimation methodology is valid to guide design of the manufacturing process for the composite-stiffened panel.展开更多
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 the National Natural Science Foundation of China(Grant No.12302229,and No.12272354)the Youth Talent Support Program of Henan Province(Grant No.2025HYTP025)+1 种基金the Postdoctoral Fellowship Program of CPSF(Grant No.GZC20232400)the Key Research Project Plan of Higher Education Institutions in Henan Province(Grant No.25A590004)。
文摘Characterized by the quasi-conically symmetric flow field,κshock wave system,and highly three-dimensional separation structures,the swept shock-wave/boundarylayer interaction(SBLI)induced by sharp fins is one of the most important phenomena in supersonic flights.An aerothermoelastic analysis is conducted on the interactions between thin-walled panels and swept SBLIs.The results of rigid wall condition,aeroelastic analysis and aerothermoelastic analysis are compared to highlight the significant influence of fluid-thermal-structural interactions on the structure and the flow field of swept SBLIs.The results show that in the aeroelastic analysis,for the material applied to the panel,although a dynamic structural response is observed,the deformation is minor and has a limited influence on the flow field.However,in the aerothermoelastic analysis,the consideration of aerodynamic heating has a significant impact on the structural response and the flow field.The deformation is an order of magnitude larger than that in the aeroelastic analysis with high vibration frequency and various main frequencies at different locations.As a result,the flow field is no longer quasi-conically symmetric.Theλshock wave system and separation structures are completely disrupted by multiple shock and expansion waves induced by the large structural deformation and become much more complex with highly three-dimensional features.This research highlights the significance of investigations on complex three-dimensional aerothermoelastic problems for supersonic flight vehicles.
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.
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funded by Science and Technology Program of Wenzhou(Y20220843).
文摘Background:Adolescent depression and school refusal(SR)are prevalent and important global concerns that need to be understood and addressed.Cross-sectional associations have been reported but prospective relationships between them remain unclear.This longitudinal study investigated the bidirectional relationships between these two problems among Chinese adolescents.Methods:A longitudinal study was conducted in Taizhou,China,surveying students of three junior high schools,three senior high schools,and one vocational high school.A total of 3882 students completed the questionnaire at baseline(T1);3167 of them completed an identical follow-up questionnaire after 6 months(T2).Depression was assessed via the Patient Health Questionnaire(PHQ-9)and SR via the modified Chinese version of The School Refusal Assessment Scale-Revised(SRAS-R).Cross-lagged panel modeling(CLPM)analysis was conducted to test the reciprocal relationships,adjusting for socio-demographic factors.Multiple group analysis was conducted to test whether the CLPM differed by gender and grade.Results:Statistically significant bidirectional relationships were found.A higher level of SR assessed at T1 is prospectively associated with a higher level of depression at T2(β=0.07,p=0.006);a higher level of depression at T1 also is prospectively associated with a higher level of SR at T2(β=0.14,p<0.001).Such models differed significantly by neither gender nor grade.Conclusion:SR and depression should be seen as each other’s mutually reinforcing association.The bidirectional relationships potentially result in a vicious cycle.Early interventions may target both problems concurrently.Future studies may involve more time points and test some mediators.
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.
基金funded by the Deanship of Scientific Research and Libraries,Princess Nourah bint Abdulrahman University,through the Program of Research Project Funding after Publication,grant No.(RPFAP-88-1445).
文摘Cooling system design applicable to more than one photovoltaic(PV)unit may be challenging due to the arrangement and geometry of the modules.Different cooling techniques are provided in this study to regulate the temperature of conductive panels that are arranged perpendicular to each other.The model uses two vented cavity systems and one L-shaped channel with ternary nanofluid enhanced non-uniform magnetic field.Their cooling performances and comparative results between different systems are provided.The finite element method is used to conduct a numerical analysis for a range of values of the following:the strength of themagnetic field(Hartmann number(Ha)between 0 and 50),the inclination of the magnetic field(γbetween 0 and 90),and the loading of nanoparticles in the base fluid(ϕbetween 0 and 0.03),taking into account both uniformand non-uniformmagnetic fields.For the L-shaped channel and vented cavities,vortex size is controlled by imposing magnetic field and adjusting its strength.Whether uniform or non-uniform magnetic field is applied affects the cooling performances for different cooling configurations.Temperature drops of the horizontal panel with different magnetic field strengths by using channel cooling,vented cavity-1 and vented cavity-2 systems for uniformmagnetic are 11℃,21.5℃,and 3℃when the reference case of Ha=0 is considered for the same cooling systems.However,they become 9.5℃,13.5℃,and 12.5℃when nonuniform magnetic field is used.In the presence of uniform magnetic field effects and changing its magnitude,the use of cooling channel in vented cavity-1 and vented cavity-2 systems results in temperature drops of 4℃,10.8℃,and 3.8℃for vertical panels.On the other hand,when non-uniform magnetic field effects are present,they become 0.5℃,2.1℃,and 9℃.For L-channel cooling,the average Nu for the horizontal panel is more affected byγ,andNu rises asγrises.With increasing nanoparticle loading of ternary nanofluid,the average panel surface temperature shows a linear drop.For the horizontal panel,the temperature declines for nanofluid at the highest loading are 4℃,10℃,and 12℃as compared to using only base fluid.The values of 5℃,7℃,and 11℃are obtained for the vertical panel.Different cooling systems’performance is estimated using artificial neural networks.The method captures the combined impact of applying non-uniformmagnetic field and nanofluid together on the cooling performancewhile accounting for varied cooling strategies for both panels.
文摘This study investigates the convergence hypothesis and stochastic dynamics of agricultural land use and ecological balance across 13 major agricultural countries from 1992 to 2022.The study's concentrated samples are Russia,the United States,the Netherlands,Brazil,Germany,China,France,Spain,Italy,Canada,Belgium,Indonesia,and India.The research uncovers notable variations in ecological balance by utilizing a comprehensive set of advanced panel unit root tests(Panel CIPS,CADF,Panel-LM,Panel-KPSS,and Bahmani-Oskooee et al.’s Panel KPSS Unit Root Test).The findings highlight significant improvements in Canada,contrasting with declines in the Netherlands,France,Germany,and the United States.The results indicate convergence in ecological balance among these countries,suggesting that agricultural practices are progressively aligning with sustainability objectives.The considered countries can determine and enact joint and collective policy actions addressing cropland sustainability.However,the univariate outcome also shows that the cropland ecological balance of Germany,China,France,Indonesia,and India does contain a unit root and stationary which means the presence of the constant-mean.The univariate actions from the mentioned governments will not promote persistent impact.Therefore,joint actions determined by the countries considered are recommended for the mentioned countries.However,the rest of the countries also enact local policies.The insights gained are critical for informing global sustainability strategies and aiding policymakers in developing effective measures to enhance agricultural practices and mitigate environmental impacts.This research provides a data-driven foundation for optimizing agricultural sustainability and supports international efforts to achieve long-term ecological stability.
基金Shenyang Pharmaceutical University Young and Middle aged Teacher Career Development Support PlanPublic Welfare Research Fund for Scientific Undertakings of Liaoning Province in 2022(Soft Science Research Plan)(No.2022JH4/10100040).
文摘Objective To study the causal relationship between R&D investment and enterprise performance of domestic pharmaceutical enterprises.Methods Panel data model was adopted for empirical analysis.Results and Conclusion Increasing the R&D investment intensity of pharmaceutical enterprises in the Yangtze River Delta and Zhejiang by 1%will increase their profit margins by 0.79%and 0.46%.On the contrary,if the profit margin increases by 1%,the R&D investment intensity will increase by 0.25%and 0.19%.If the profit margin of pharmaceutical enterprises in Beijing,Tianjin,Hebei,Chengdu,Chongqing and other regions increases by 1%,the R&D investment intensity will increase by 0.14%,0.07%and 0.1%,respectively,which are lower than those in the Yangtze River Delta and Zhejiang.The relationship between R&D investment and enterprise performance of pharmaceutical enterprises in the Yangtze River Delta and Zhejiang Province is Granger causality,showing a two-way positive effect.Profits and R&D investment of pharmaceutical enterprises in Beijing,Tianjin,Hebei,Chengdu,Chongqing and other regions are also Granger causality.But in the Pearl River Delta,profits and R&D investment have not passed the stability test,it is impossible to determine the causality between them.
文摘The buckling behavior of stiffened panels is significantly influenced by material and geometric defects,making it a critical factor in ensuring structural integrity and safety.These panels are widely used in mechanical,aerospace,marine,and civil engineering applications due to their ability to enhance bending stiffness with minimal additional weight.Under high loads or stress concentrations,localized structural failures can initiate global buckling in stiffened panels.This study investigates how such defects affect the critical buckling load,stiffness,and thickness of stiffened panels.Two finite element analyses were conducted:a linear analysis to identify the initial buckling mode and a nonlinear analysis using the Riks algorithm in Abaqus CAE,incorporating localized imperfections.The simulations show that material and geometric defects can reduce buckling resistance depending on their severity.
基金supported by the Shanghai New Three-year Action Plan for Public Health(Grant No.GWV-10.1-XK16)the US National Institute on Aging(RO1-AGO34479).
文摘In 2019,China had over 13.14 million dementia cases,with incidence rates of(56.47–207.08)/100,000[1].Early cognitive impairment—a key dementia symptom—reduces quality of life,increases care dependence,and lowers survival in older adults[2].A decline in physical function can also be observed in older adults with increasing age.Grip strength has been shown to be a marker of overall physiological function in older adults.
文摘Objective:This study aimed to examine the influence of behavioral lifestyle factors on recent episodic memory retention capacity among young-old adults(aged 60-69 years)in China.The findings provide scientific evidence to inform proactive strategies to mitigate cognitive decline risk within China’s rapidly aging population.Methods:Utilizing data from the 2022 wave of the China Family Panel Studies(CFPS),a total of 2,772 adults aged 60-69 were included in the analytical sample.Recent episodic memory retention capacity(scored 0-5 points,based on self-reported assessment)served as the dependent variable.Six categories of behavioral lifestyle indicators(including exercise frequency,sleep quality,dietary patterns,etc.)were analyzed as independent variables.Associations were assessed using multivariate ordinal logistic regression models,controlling for relevant covariates.Results:Self-reported potential impairment in recent episodic memory was identified by 47.19%of respondents.Multivariate analysis revealed significant associations between behavioral lifestyle factors and memory retention capacity.Regular exercise(OR=1.297,95%CI:1.118-1.504),meat consumption(OR=1.765,95%CI:1.393-2.237),regular reading habits(OR=1.599,95%CI:1.283-1.992),and internet use(OR=1.413,95%CI:1.217-1.641)emerged as significant protective factors.Abnormal sleep duration was detrimentally associated with retention capacity(too short:OR=0.728,95%CI:0.591-0.897;too long:OR=0.810,95%CI:0.670-0.980).Significant associations were also observed for control variables:urban residence(OR=1.270,95%CI:1.100-1.467),high school education or above(OR=1.543,95%CI:1.293-1.841),and better self-rated health status(OR=1.156,95%CI:1.089-1.227)were positively correlated with better memory retention.Conclusions:Optimal sleep duration,regular physical exercise,meat intake,habitual reading,and internet engagement positively predict self-assessed recent episodic memory retention capacity in Chinese young-old adults.These findings underscore the potential for multi-faceted lifestyle interventions to enhance cog-nitive health in aging populations.Specifically,strategies should encompass community-based sleep hygiene management,tailored nutritional interventions(especially promoting adequate protein sources like meat),enhanced digital literacy and internet accessibility programs,and the promotion of age-appropriate physical activity initiatives.Furthermore,implementing culturally responsive strategies adapted to urban-rural contexts-such as deploying“mobile cognitive health units”in rural areas and fostering digital reading platforms in urban settings-is recommended to optimize intervention effectiveness.
基金funded by the Spanish Ministerio de Ciencia,Innovación y Universidades,grant number RTC2019-007364-3(FPGM)by the Comunidad de Madrid through the direct grant with ref.SI4/PJI/2024-00233 for the promotion of research and technology transfer at the Universidad Autónoma de Madrid。
文摘Due to the continuous increase in global energy demand,photovoltaic solar energy generation and associated maintenance requirements have significantly expanded.One critical maintenance challenge in photovoltaic installations is detecting hot spots,localized overheating defects in solar cells that drastically reduce efficiency and can lead to permanent damage.Traditional methods for detecting these defects rely on manual inspections using thermal imaging,which are costly,labor-intensive,and impractical for large-scale installations.This research introduces an automated hybrid system based on two specialized convolutional neural networks deployed in a cascaded architecture.The first convolutional neural network efficiently detects and isolates individual solar panels from high-resolution aerial thermal images captured by drones.Subsequently,a second,more advanced convolutional neural network accurately classifies each isolated panel as either defective or healthy,effectively distinguishing genuine thermal anomalies from false positives caused by reflections or glare.Experimental validation on a real-world dataset comprising thousands of thermal images yielded exceptional accuracy,significantly reducing inspection time,costs,and the likelihood of false defect detections.This proposed system enhances the reliability and efficiency of photovoltaic plant inspections,thus contributing to improved operational performance and economic viability.
基金the National Natural Science Foundation of China(Grant Nos.11972096,12372127 and 12202085)the Fundamental Research Funds for the Central Universities(Grant No.2022CDJQY004)+4 种基金Chongqing Natural Science Foundation(Grant No.cstc2021ycjh-bgzxm0117)China Postdoctoral Science Foundation(Grant No.2022M720562)Chongqing Postdoctoral Science Foundation(Grant No.2021XM3022)supported by the opening project of State Key Laboratory of Explosion Science and Technology(Beijing Institute of Technology)The opening project number is KFJJ23-18 M。
文摘This study systematically examines the energy dissipation mechanisms and ballistic characteristics of foam sandwich panels(FSP)under high-velocity impact using the explicit non-linear finite element method.Based on the geometric topology of the FSP system,three FSP configurations with the same areal density are derived,namely multi-layer,gradient core and asymmetric face sheet,and three key structural parameters are identified:core thickness(t_(c)),face sheet thickness(t_(f))and overlap face/core number(n_(o)).The ballistic performance of the FSP system is comprehensively evaluated in terms of the ballistic limit velocity(BLV),deformation modes,energy dissipation mechanism,and specific penetration energy(SPE).The results show that the FSP system exhibits a significant configuration dependence,whose ballistic performance ranking is:asymmetric face sheet>gradient core>multi-layer.The mass distribution of the top and bottom face sheets plays a critical role in the ballistic resistance of the FSP system.Both BLV and SPE increase with tf,while the raising tcor noleads to an increase in BLV but a decrease in SPE.Further,a face-core synchronous enhancement mechanism is discovered by the energy dissipation analysis,based on which the ballistic optimization procedure is also conducted and a design chart is established.This study shed light on the anti-penetration mechanism of the FSP system and might provide a theoretical basis for its engineering application.
基金supported by the National Natural Science Foundation of China(Grant No.52079046).
文摘Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in China.Safety control is essential to long-term operation of these dams.This study employed the flexibility coefficient and plastic complementary energy norm to assess the structural safety of arch dams.A comprehensive analysis was conducted,focusing on differences among conventional methods in characterizing the structural behavior of the Xiaowan arch dam in China.Subsequently,the spatiotemporal characteristics of the measured performance of the Xiaowan dam were explored,including periodicity,convergence,and time-effect characteristics.These findings revealed the governing mechanism of main factors.Furthermore,a heterogeneous spatial panel vector model was developed,considering both common factors and specific factors affecting the safety and performance of arch dams.This model aims to comprehensively illustrate spatial heterogeneity between the entire structure and local regions,introducing a specific effect quantity to characterize local deformation differences.Ultimately,the proposed model was applied to the Xiaowan arch dam,accurately quantifying the spatiotemporal heterogeneity of dam performance.Additionally,the spatiotemporal distri-bution characteristics of environmental load effects on different parts of the dam were reasonably interpreted.Validation of the model prediction enhances its credibility,leading to the formulation of health diagnosis criteria for future long-term operation of the Xiaowan dam.The findings not only enhance the predictive ability and timely control of ultrahigh arch dams'performance but also provide a crucial basis for assessing the effectiveness of engineering treatment measures.
基金the Hainan Yazhou Bay Seed Laboratory(B21Y10209 and B22C10212)China Postdoctoral Science Foundation(2022M713433)+1 种基金National Natural Science Foundation of China(31861143003)Innovation Program of Chinese Academy of Agricultural Sciences.
文摘A large amount of genome-wide association study(GWAS)panels together with quantitative-trait locus(QTL)information associated with breeding-targeted traits have been described in wheat(Triticum aestivum L.).However,the application of mapping results from a GWAS panel to conventional wheat breeding remains a challenge.In this study,we first report a general genetic map which was constructed from 44 published linkage maps.It permits the estimation of genetic distances between any two genetic loci with physical map positions,thereby unifying the linkage relationships between QTL,genes,and genomic markers from multiple genetic populations.Second,we describe QTL mapping in a wheat GWAS panel of 688 accessions,identifying 77 QTL associated with 12 yield and grain-quality traits.Because these QTL have known physical map positions,they could be mapped onto the general map.Finally,we present a design approach to wheat breeding by using known QTL information and computer simulation.Potential crosses between parents in the GWAS panel may be evaluated by the relative frequency of the target genotype,trait correlations in simulated progeny populations,and genetic gain of selected progenies.It is possible to simultaneously improve yield and grain quality by suitable parental selection,progeny population size,and progeny selection scheme.Applying the design approach will allow identifying the most promising crosses and selection schemes in advance of the field experiment,increasing predictability and efficiency in wheat breeding.
文摘The primary goal of this study is to fully grasp the production flow of the new processing technologies for manufacturing composite stiffened panels incorporating cost as one of the design variables early in the design process. An approach is presented to determine the optimum process for cost as objective function. A cost estimation model is established based on the integrally molding process. In the model,the cost drivers which are related to the manufacture processes in terms of material,labor,tool and equipment costs are taken into account. At the same time,estimation software combined computer is developed to aid optimization design. A case of manufacturing composite stiffened panels with T-shaped stiffeners is examined. Excellent agreement shows the optimum process for cost is obtained for the composite stiffened panel with cocuring. It is also revealed that the estimation software combined computer is efficient. The estimation methodology is valid to guide design of the manufacturing process for the composite-stiffened panel.
