The Hengduan Mountains are susceptible to hydrological disasters,with precipitation representing a significant risk factor.For effective disaster mitigation strategies,accurate rainfall simulation is essential,typical...The Hengduan Mountains are susceptible to hydrological disasters,with precipitation representing a significant risk factor.For effective disaster mitigation strategies,accurate rainfall simulation is essential,typically achieved through the use of numerical models.Some research has indicated that using a convection-permitting model(CPM)at high resolution(<4 km)could provide more precise rainfall estimates than traditional cumulus parameterization schemes(CPs)at lower resolutions,but CPM demands substantial computational resources.Therefore,to assess whether CPM maintains superior simulation accuracy,this study employed the Weather Research and Forecasting(WRF)model to simulate summer precipitation over the Hengduan Mountains in 2009,comparing CPM(4 km)and CPs(10 km)resolutions.The simulations were evaluated against satellite observations to quantify their performance differences.The results showed that all simulations overestimated amounts and frequency.The CPM outperformed most CPs,except the Tiedtke scheme,which exhibited Root Mean Square Errors(RMSEs)of 2.51 mm·day-1 for amount and 5.63%for frequency.The CPM had slightly higher RMSEs of 2.80 mm·day-1 and 6.98%,respectively.Both CPM and Tiedtke captured the spatial distribution of precipitation,but overestimations occurred in central and southern regions and underestimations in river valleys.While Tiedtke demonstrated superiority in various aspects,CPM provided more detail.Additionally,the study noted significant differences in diurnal variation at intermediate altitudes and found correlations between rainfall amounts and convective available potential energy(CAPE),frequency,and outgoing longwave radiation(OLR),respectively.Consequently,the Tiedtke scheme is suggested as a more resource-efficient alternative to CPM for simulating precipitation in the Hengduan Mountains.展开更多
The deep potential(DP)is an innovative approach based on deep learning that uses ab initio calculation data derived from density functional theory(DFT),to create high-accuracy potential functions for various materials...The deep potential(DP)is an innovative approach based on deep learning that uses ab initio calculation data derived from density functional theory(DFT),to create high-accuracy potential functions for various materials.Platinum(Pt)is a rare metal with significant potential in energy and catalytic applications,However,there are challenges in accurately capturing its physical properties due to high experimental costs and the limitations of traditional empirical methods.This study employs deep learning methods to construct high-precision potential models for single-element systems of Pt and validates their predictive performance in complex environments.The newly developed DP is highly consistent with DFT results in predicting the stable phases,lattice constants,surface energies,and phonons dispersion relations of Pt,demonstrating outstanding quantum-level accuracy.Additionally,the complex phase transitions and domain formations of Pt are extensively and quantitatively analyzed.Molecular dynamic simulations utilizing the DP approach show that Pt’s face-centered cubic(FCC)structure undergoes a phase transition from solid to liquid at its melting point of 1986 K,this is in close agreement with the experimental value of 2041.5 K.Increased temperature enhances the diffusion of Pt atoms,with a self-diffusion coefficient of 1.17×10-11 m2/s at the melting point,comparable to that of other FCC metals.This result can be utilized for the precise analysis of the fundamental properties of the rare metal Pt at the microscopic scale,and it facilitates the development of binary or multi-component deep potential models that include Pt.展开更多
Researching and comprehending the characteristics of destructive seismic motions is essential for the seismic design of critical infrastructure.This study employs historical data from the M 7.5 earthquake that occurre...Researching and comprehending the characteristics of destructive seismic motions is essential for the seismic design of critical infrastructure.This study employs historical data from the M 7.5 earthquake that occurred in 1850 to simulate the impacts of a M 7.5 event on hydropower stations located in proximity to Xichang.Key factors taken into account in the simulation of seismic motion encompass uncertainties,mixed-source models,and the placement of asperities.Through these simulations,we acquired the peak ground acceleration(PGA),acceleration time histories,and acceleration response spectra for the hydropower facilities affected by the earthquake.To perform a comprehensive analysis,we utilized a multi-scenario stochastic finite fault simulation method to estimate parameters including the minimum,average,and maximum values of PGA and pseudo-spectral acceleration(PSA)response spectra.Additionally,we assessed the 50^(th),84^(th),and 95^(th)percentiles values of the peak ground acceleration and pseudo-spectral acceleration response spectra.The simulation results also include peak ground acceleration field maps and peak ground velocity(PGV)field maps and intensity distribution maps pertaining to the earthquake.The findings demonstrate that the intensity maps produced through the stochastic finite fault method closely correspond with the intensity contour maps published of historical seismic records.These findings offer significant insights for the seismic safety evaluation and design of the specified hydropower stations.Moreover,this multi-scenario methodology can be effectively utilized for other critical infrastructure projects to derive dependable seismic motion parameters.展开更多
1.Introduction Computational Fluid Dynamics-Discrete Element Method(CFD-DEM)is a powerful tool for simulating dense gas-solid reacting flows,which is essential in combustion,metallurgy,and waste management.Traditional...1.Introduction Computational Fluid Dynamics-Discrete Element Method(CFD-DEM)is a powerful tool for simulating dense gas-solid reacting flows,which is essential in combustion,metallurgy,and waste management.Traditional methods face challenges in CFD-DEM modeling of dense gas-solid flows due to multi-scale characteristics,limiting resolution and creating simulation bottlenecks.By integrating fluid dynamics and particle behavior,it optimizes industrial processes.This review highlights advancements,applications,and challenges,emphasizing its role in sustainable engineering.展开更多
Basic structure and algorithm of leaf mechanism photosynthesis model were described in first part of this study based on former researcher results. Then, considering some environmental factors influencing on leaf ph...Basic structure and algorithm of leaf mechanism photosynthesis model were described in first part of this study based on former researcher results. Then, considering some environmental factors influencing on leaf photosynthesis, three numerical sensitivity experiments were carried out. We simulated the sing le leaf net CO2 assimilation, which acts as a function of different light, carbo n dioxide and temperature conditions. The relationships between leaf net photosy nthetic rate of C3 and C4 plant with CO2 concentration intercellular, leaf tempe rature, and photosynthetic active radiation (PAR) were presented, respectively. The results show the numerical experiment may indicate the main characteristic o f plant photosynthesis in C3 and C4 plant, and further can be used to integrate with the regional climate model and act as land surface process scheme, and bett er understand the interaction between vegetation and atmosphere.展开更多
Through system analysis of typical explosive trains in various fuses, physical and correspondent mathematical models of typical explosive trains are established, based on mass conservation, momentum conservation, ener...Through system analysis of typical explosive trains in various fuses, physical and correspondent mathematical models of typical explosive trains are established, based on mass conservation, momentum conservation, energy conservation and so on. MAZE and DYNA2D program is used to dispose these models and results of the simulating of elements of explosive trains in a typical fuse are obtained. It is helpful for designing fuses.展开更多
Utilizing finite element analysis,the ballistic protection provided by a combination of perforated D-shaped and base armor plates,collectively referred to as radiator armor,is evaluated.ANSYS Explicit Dynamics is empl...Utilizing finite element analysis,the ballistic protection provided by a combination of perforated D-shaped and base armor plates,collectively referred to as radiator armor,is evaluated.ANSYS Explicit Dynamics is employed to simulate the ballistic impact of 7.62 mm armor-piercing projectiles on Aluminum AA5083-H116 and Steel Secure 500 armors,focusing on the evaluation of material deformation and penetration resistance at varying impact points.While the D-shaped armor plate is penetrated by the armor-piercing projectiles,the combination of the perforated D-shaped and base armor plates successfully halts penetration.A numerical model based on the finite element method is developed using software such as SolidWorks and ANSYS to analyze the interaction between radiator armor and bullet.The perforated design of radiator armor is to maintain airflow for radiator function,with hole sizes smaller than the bullet core diameter to protect radiator assemblies.Predictions are made regarding the brittle fracture resulting from the projectile core′s bending due to asymmetric impact,and the resulting fragments failed to penetrate the perforated base armor plate.Craters are formed on the surface of the perforated D-shaped armor plate due to the impact of projectile fragments.The numerical model accurately predicts hole growth and projectile penetration upon impact with the armor,demonstrating effective protection of the radiator assemblies by the radiator armor.展开更多
BACKGROUND Orthopaedic surgical education has traditionally depended on the apprenticeship model of“see one,do one,teach one”.However,reduced operative exposure,stricter work-hour regulations,medicolegal constraints...BACKGROUND Orthopaedic surgical education has traditionally depended on the apprenticeship model of“see one,do one,teach one”.However,reduced operative exposure,stricter work-hour regulations,medicolegal constraints,and patient safety concerns have constrained its practicality.Simulation-based training has become a reliable,safe,and cost-efficient alternative.Dry lab techniques,especially virtual and augmented reality,make up 78%of current dry lab research,whereas wet labs still set the standard for anatomical realism.AIM To evaluate the effectiveness,limitations,and future directions of wet and dry lab simulation in orthopaedic training.METHODS A scoping review was carried out across four databases-PubMed,Cochrane Library,Web of Science,and EBSCOhost-up to 2025.Medical Subject Headings included:"Orthopaedic Education","Wet Lab","Dry Lab","Simulation Training","Virtual Reality",and"Surgical Procedure".Eligible studies focused on orthopaedic or spinal surgical education,employed wet or dry lab techniques,and assessed training effectiveness.Exclusion criteria consisted of non-English publications,abstracts only,non-orthopaedic research,and studies unrelated to simulation.Two reviewers independently screened titles,abstracts,and full texts,resolving discrepancies with a third reviewer.RESULTS From 1851 records,101 studies met inclusion:78 on dry labs,7 on wet labs,4 on both.Virtual reality(VR)simulations were most common,with AI increasingly used for feedback and assessment.Cadaveric training remains the gold standard for accuracy and tactile feedback,while dry labs-especially VR-offer scalability,lower cost(40%-60%savings in five studies),and accessibility for novices.Senior residents prefer wet labs for complex tasks;juniors favour dry labs for basics.Challenges include limited transferability data,lack of standard outcome metrics,and ethical concerns about cadaver use and AI assessment.CONCLUSION Wet and dry labs each have unique strengths in orthopaedic training.A hybrid approach combining both,supported by standardised assessments and outcome studies,is most effective.Future efforts should aim for uniform reporting,integrating new technologies,and policy support for hybrid curricula to enhance skills and patient care.展开更多
基金supported by the National Natural Science Foundation of China(No.42475101)Open Research Fund of Heavy Rain and Drought-Flood Disasters in Plateau and Basin Key Laboratory of Sichuan Province(No.SZKT202303)+1 种基金the Science and Technology Research Program of Institute of Mountain Hazards and Environment,Chinese Academy of Sciences(No.IMHE-ZDRW-06)support by the National Key Scientific and Technological Infrastructure project“Earth System Numerical Simulation Facility”(EarthLab)。
文摘The Hengduan Mountains are susceptible to hydrological disasters,with precipitation representing a significant risk factor.For effective disaster mitigation strategies,accurate rainfall simulation is essential,typically achieved through the use of numerical models.Some research has indicated that using a convection-permitting model(CPM)at high resolution(<4 km)could provide more precise rainfall estimates than traditional cumulus parameterization schemes(CPs)at lower resolutions,but CPM demands substantial computational resources.Therefore,to assess whether CPM maintains superior simulation accuracy,this study employed the Weather Research and Forecasting(WRF)model to simulate summer precipitation over the Hengduan Mountains in 2009,comparing CPM(4 km)and CPs(10 km)resolutions.The simulations were evaluated against satellite observations to quantify their performance differences.The results showed that all simulations overestimated amounts and frequency.The CPM outperformed most CPs,except the Tiedtke scheme,which exhibited Root Mean Square Errors(RMSEs)of 2.51 mm·day-1 for amount and 5.63%for frequency.The CPM had slightly higher RMSEs of 2.80 mm·day-1 and 6.98%,respectively.Both CPM and Tiedtke captured the spatial distribution of precipitation,but overestimations occurred in central and southern regions and underestimations in river valleys.While Tiedtke demonstrated superiority in various aspects,CPM provided more detail.Additionally,the study noted significant differences in diurnal variation at intermediate altitudes and found correlations between rainfall amounts and convective available potential energy(CAPE),frequency,and outgoing longwave radiation(OLR),respectively.Consequently,the Tiedtke scheme is suggested as a more resource-efficient alternative to CPM for simulating precipitation in the Hengduan Mountains.
基金supported by the Kunming University of Science and Technology“Double First-Class”Joint Special Project(Grant No.202101BE070001-011)Yunnan Fundamental Research Projects(202201BE070001-008,202201AT070192)+5 种基金National Natural Science Foundation of China(52402077)Shaanxi Province Key R&D Program(2021ZDLGY11-08)Open Project of Shaanxi Laboratory(2021SXsyS01-05)Open Project of Yunnan Precious Metals Laboratory(YPML-2023050240)National Natural Science Foundation of China(Grant No.52462009)Yunnan Fundamental Research Projects(Grant Nos.202201AT070192,202101BE070001-011).
文摘The deep potential(DP)is an innovative approach based on deep learning that uses ab initio calculation data derived from density functional theory(DFT),to create high-accuracy potential functions for various materials.Platinum(Pt)is a rare metal with significant potential in energy and catalytic applications,However,there are challenges in accurately capturing its physical properties due to high experimental costs and the limitations of traditional empirical methods.This study employs deep learning methods to construct high-precision potential models for single-element systems of Pt and validates their predictive performance in complex environments.The newly developed DP is highly consistent with DFT results in predicting the stable phases,lattice constants,surface energies,and phonons dispersion relations of Pt,demonstrating outstanding quantum-level accuracy.Additionally,the complex phase transitions and domain formations of Pt are extensively and quantitatively analyzed.Molecular dynamic simulations utilizing the DP approach show that Pt’s face-centered cubic(FCC)structure undergoes a phase transition from solid to liquid at its melting point of 1986 K,this is in close agreement with the experimental value of 2041.5 K.Increased temperature enhances the diffusion of Pt atoms,with a self-diffusion coefficient of 1.17×10-11 m2/s at the melting point,comparable to that of other FCC metals.This result can be utilized for the precise analysis of the fundamental properties of the rare metal Pt at the microscopic scale,and it facilitates the development of binary or multi-component deep potential models that include Pt.
基金the support of National Natural Science Foundation of China(Grant Numbers 52192675 and 52378541)。
文摘Researching and comprehending the characteristics of destructive seismic motions is essential for the seismic design of critical infrastructure.This study employs historical data from the M 7.5 earthquake that occurred in 1850 to simulate the impacts of a M 7.5 event on hydropower stations located in proximity to Xichang.Key factors taken into account in the simulation of seismic motion encompass uncertainties,mixed-source models,and the placement of asperities.Through these simulations,we acquired the peak ground acceleration(PGA),acceleration time histories,and acceleration response spectra for the hydropower facilities affected by the earthquake.To perform a comprehensive analysis,we utilized a multi-scenario stochastic finite fault simulation method to estimate parameters including the minimum,average,and maximum values of PGA and pseudo-spectral acceleration(PSA)response spectra.Additionally,we assessed the 50^(th),84^(th),and 95^(th)percentiles values of the peak ground acceleration and pseudo-spectral acceleration response spectra.The simulation results also include peak ground acceleration field maps and peak ground velocity(PGV)field maps and intensity distribution maps pertaining to the earthquake.The findings demonstrate that the intensity maps produced through the stochastic finite fault method closely correspond with the intensity contour maps published of historical seismic records.These findings offer significant insights for the seismic safety evaluation and design of the specified hydropower stations.Moreover,this multi-scenario methodology can be effectively utilized for other critical infrastructure projects to derive dependable seismic motion parameters.
文摘1.Introduction Computational Fluid Dynamics-Discrete Element Method(CFD-DEM)is a powerful tool for simulating dense gas-solid reacting flows,which is essential in combustion,metallurgy,and waste management.Traditional methods face challenges in CFD-DEM modeling of dense gas-solid flows due to multi-scale characteristics,limiting resolution and creating simulation bottlenecks.By integrating fluid dynamics and particle behavior,it optimizes industrial processes.This review highlights advancements,applications,and challenges,emphasizing its role in sustainable engineering.
基金Natural Science Foundation of China (Grant No. 39900084)
文摘Basic structure and algorithm of leaf mechanism photosynthesis model were described in first part of this study based on former researcher results. Then, considering some environmental factors influencing on leaf photosynthesis, three numerical sensitivity experiments were carried out. We simulated the sing le leaf net CO2 assimilation, which acts as a function of different light, carbo n dioxide and temperature conditions. The relationships between leaf net photosy nthetic rate of C3 and C4 plant with CO2 concentration intercellular, leaf tempe rature, and photosynthetic active radiation (PAR) were presented, respectively. The results show the numerical experiment may indicate the main characteristic o f plant photosynthesis in C3 and C4 plant, and further can be used to integrate with the regional climate model and act as land surface process scheme, and bett er understand the interaction between vegetation and atmosphere.
文摘Through system analysis of typical explosive trains in various fuses, physical and correspondent mathematical models of typical explosive trains are established, based on mass conservation, momentum conservation, energy conservation and so on. MAZE and DYNA2D program is used to dispose these models and results of the simulating of elements of explosive trains in a typical fuse are obtained. It is helpful for designing fuses.
文摘Utilizing finite element analysis,the ballistic protection provided by a combination of perforated D-shaped and base armor plates,collectively referred to as radiator armor,is evaluated.ANSYS Explicit Dynamics is employed to simulate the ballistic impact of 7.62 mm armor-piercing projectiles on Aluminum AA5083-H116 and Steel Secure 500 armors,focusing on the evaluation of material deformation and penetration resistance at varying impact points.While the D-shaped armor plate is penetrated by the armor-piercing projectiles,the combination of the perforated D-shaped and base armor plates successfully halts penetration.A numerical model based on the finite element method is developed using software such as SolidWorks and ANSYS to analyze the interaction between radiator armor and bullet.The perforated design of radiator armor is to maintain airflow for radiator function,with hole sizes smaller than the bullet core diameter to protect radiator assemblies.Predictions are made regarding the brittle fracture resulting from the projectile core′s bending due to asymmetric impact,and the resulting fragments failed to penetrate the perforated base armor plate.Craters are formed on the surface of the perforated D-shaped armor plate due to the impact of projectile fragments.The numerical model accurately predicts hole growth and projectile penetration upon impact with the armor,demonstrating effective protection of the radiator assemblies by the radiator armor.
文摘BACKGROUND Orthopaedic surgical education has traditionally depended on the apprenticeship model of“see one,do one,teach one”.However,reduced operative exposure,stricter work-hour regulations,medicolegal constraints,and patient safety concerns have constrained its practicality.Simulation-based training has become a reliable,safe,and cost-efficient alternative.Dry lab techniques,especially virtual and augmented reality,make up 78%of current dry lab research,whereas wet labs still set the standard for anatomical realism.AIM To evaluate the effectiveness,limitations,and future directions of wet and dry lab simulation in orthopaedic training.METHODS A scoping review was carried out across four databases-PubMed,Cochrane Library,Web of Science,and EBSCOhost-up to 2025.Medical Subject Headings included:"Orthopaedic Education","Wet Lab","Dry Lab","Simulation Training","Virtual Reality",and"Surgical Procedure".Eligible studies focused on orthopaedic or spinal surgical education,employed wet or dry lab techniques,and assessed training effectiveness.Exclusion criteria consisted of non-English publications,abstracts only,non-orthopaedic research,and studies unrelated to simulation.Two reviewers independently screened titles,abstracts,and full texts,resolving discrepancies with a third reviewer.RESULTS From 1851 records,101 studies met inclusion:78 on dry labs,7 on wet labs,4 on both.Virtual reality(VR)simulations were most common,with AI increasingly used for feedback and assessment.Cadaveric training remains the gold standard for accuracy and tactile feedback,while dry labs-especially VR-offer scalability,lower cost(40%-60%savings in five studies),and accessibility for novices.Senior residents prefer wet labs for complex tasks;juniors favour dry labs for basics.Challenges include limited transferability data,lack of standard outcome metrics,and ethical concerns about cadaver use and AI assessment.CONCLUSION Wet and dry labs each have unique strengths in orthopaedic training.A hybrid approach combining both,supported by standardised assessments and outcome studies,is most effective.Future efforts should aim for uniform reporting,integrating new technologies,and policy support for hybrid curricula to enhance skills and patient care.
