Recent advancements in computational and database technologies have led to the exponential growth of large-scale medical datasets,significantly increasing data complexity and dimensionality in medical diagnostics.Effi...Recent advancements in computational and database technologies have led to the exponential growth of large-scale medical datasets,significantly increasing data complexity and dimensionality in medical diagnostics.Efficient feature selection methods are critical for improving diagnostic accuracy,reducing computational costs,and enhancing the interpretability of predictive models.Particle Swarm Optimization(PSO),a widely used metaheuristic inspired by swarm intelligence,has shown considerable promise in feature selection tasks.However,conventional PSO often suffers from premature convergence and limited exploration capabilities,particularly in high-dimensional spaces.To overcome these limitations,this study proposes an enhanced PSO framework incorporating Orthogonal Initializa-tion and a Crossover Operator(OrPSOC).Orthogonal Initialization ensures a diverse and uniformly distributed initial particle population,substantially improving the algorithm’s exploration capability.The Crossover Operator,inspired by genetic algorithms,introduces additional diversity during the search process,effectively mitigating premature convergence and enhancing global search performance.The effectiveness of OrPSOC was rigorously evaluated on three benchmark medical datasets—Colon,Leukemia,and Prostate Tumor.Comparative analyses were conducted against traditional filter-based methods,including Fast Clustering-Based Feature Selection Technique(Fast-C),Minimum Redundancy Maximum Relevance(MinRedMaxRel),and Five-Way Joint Mutual Information(FJMI),as well as prominent metaheuristic algorithms such as standard PSO,Ant Colony Optimization(ACO),Comprehensive Learning Gravitational Search Algorithm(CLGSA),and Fuzzy-Based CLGSA(FCLGSA).Experimental results demonstrated that OrPSOC consistently outperformed these existing methods in terms of classification accuracy,computational efficiency,and result stability,achieving significant improvements even with fewer selected features.Additionally,a sensitivity analysis of the crossover parameter provided valuable insights into parameter tuning and its impact on model performance.These findings highlight the superiority and robustness of the proposed OrPSOC approach for feature selection in medical diagnostic applications and underscore its potential for broader adoption in various high-dimensional,data-driven fields.展开更多
Physics-informed neural networks(PINNs)have shown considerable promise for performing numerical simulations in fluid mechanics.They provide mesh-free,end-to-end approaches by embedding physical laws into their loss fu...Physics-informed neural networks(PINNs)have shown considerable promise for performing numerical simulations in fluid mechanics.They provide mesh-free,end-to-end approaches by embedding physical laws into their loss functions.However,when addressing complex flow problems,PINNs still face some challenges such as activation saturation and vanishing gradients in deep network training,leading to slow convergence and insufficient prediction accuracy.We present physics-informed neural networks incorporating lattice Boltzmann method optimized by tanh robust weight initialization(T-PINN-LBM)to address these challenges.This approach fuses the mesoscopic lattice Boltzmann model with the automatic differentiation framework of PINNs.It also implements a tanh robust weight initialization method derived from fixed point analysis.This model effectively mitigates activation and gradient decay in deep networks,improving convergence speed and data efficiency in multiscale flow simulations.We validate the effectiveness of the model on the classical arithmetic example of lid-driven cavity flow.Compared to the traditional Xavier initialized PINN and PINN-LBM,T-PINNLBM reduces the mean absolute error(MAE)by one order of magnitude at the same network depth and maintains stable convergence in deeper networks.The results demonstrate that this model can accurately capture complex flow structures without prior data,providing a new feasible pathway for data-free driven fluid simulation.展开更多
This paper presents an analysis of an equilateral triangular array formation initialization for space-based gravitational wave observatory(GWO)near Lagrange points in the circular-restricted three-body problem.A stabl...This paper presents an analysis of an equilateral triangular array formation initialization for space-based gravitational wave observatory(GWO)near Lagrange points in the circular-restricted three-body problem.A stable configuration is essential for the continuous observation of gravitational waves(GWs).However,the motion near the collinear libration points is highly unstable.This problem is examined by output regulation theory.Using the tracking aspect,the equilateral triangular array formation is established in two periods and the fuel consumption is calculated.Furthermore,the natural evolution of the formation without control input is analyzed,and the effective stability duration is quantified to determine the timing of control interventions.Finally,to observe the GWs in same direction with different frequency bands,scale reconfiguration is employed.展开更多
During the initial impoundment period of a canyon-shaped reservoir,the water body fluctuated violently regarding water level,hydrological condition,and thermal stratification.These variations may alter the structure o...During the initial impoundment period of a canyon-shaped reservoir,the water body fluctuated violently regarding water level,hydrological condition,and thermal stratification.These variations may alter the structure of phytoplankton community,resulting in algal blooms and seriously threatening the ecological security of the reservoir.It is of great significance to understand the continuous changes of phytoplankton in the initial impoundment period for the protection of reservoir water quality.Therefore,a two-year in-situ monitoring study was conducted on water quality and phytoplankton in a representative canyonshaped reservoir named Sanhekou and the interannual changes of phytoplankton community and its response to environmental changes during the initial impoundment period were discussed at taxonomic versus functional classification levels.The results showed that the total nitrogen and permanganate index levels were relatively high in the first year due to rapid water storage and heavy rainfall input,and the more stable hydrological conditions in the second year promoted the increase of algae density and the transformation of community,and the proportion of cyanobacteria increased significantly.The succession order of phytoplankton in the first year of the initial impoundment periodwas Chlorophyta-Bacillariophyta-Chlorophyta,or J/F/X1-P/MP/W1-A/X1/MP,respectively.And the succession order in the second year was Cyanobacteria/Chlorophyta-Bacillariophyta-Chlorophyta,or L_(M)/G/P-P/A/X1-X1/J/G.Water temperature,relativewater column stability,mixing depth,and pHwere crucial factors affecting phytoplankton community succession.This study revealed the interannual succession law and driving factors of phytoplankton in the initial impoundment period and provided an important reference for the operation management and ecological protection of canyon-shaped reservoirs.展开更多
Evaluation of hydromechanical shear behavior of unsaturated soils is still a challenging issue. The time and cost needed for conducting precise experimental investigation on shear behavior of unsaturated soils have en...Evaluation of hydromechanical shear behavior of unsaturated soils is still a challenging issue. The time and cost needed for conducting precise experimental investigation on shear behavior of unsaturated soils have encouraged several investigators to develop analytical, empirical, or semi-empirical models for predicting the shear behavior of unsaturated soils. However, most of the previously proposed models are for specimens subjected to the isotropic state of stress, without considering the effect of initial shear stress. In this study, a hydromechanical constitutive model is proposed for unsaturated collapsible soils during shearing, with consideration of the effect of the initial shear stress. The model implements an effective stress-based disturbed state concept (DSC) to predict the stress-strain behavior of the soil. Accordingly, material/state variables were defined for both the start of the shearing stage and the critical state of the soil. A series of laboratory tests was performed using a fully automated unsaturated triaxial device to verify the proposed model. The experimental program included 23 suction-controlled unsaturated triaxial shear tests on reconstituted specimens of Gorgan clayey loess wetted to different levels of suctions under both isotropic and anisotropic stress states. The results show excellent agreement between the prediction by the proposed model and the experimental results.展开更多
We study the two-dimensional(2D)Cauchy problem of nonhomogeneous Boussinesq system for magnetohydrodynamics convection without heat diffusion in the whole plane.Based on delicate weighted estimates,we derive the globa...We study the two-dimensional(2D)Cauchy problem of nonhomogeneous Boussinesq system for magnetohydrodynamics convection without heat diffusion in the whole plane.Based on delicate weighted estimates,we derive the global existence and uniqueness of strong solutions.In particular,the initial data can be arbitrarily large and the initial density may contain vacuum states and even have compact support.展开更多
There is curiosity and awareness throughout the world regarding the role of Information and Communication technologies. This is felt in each and every section of society. Several studies have confirmed and considered ...There is curiosity and awareness throughout the world regarding the role of Information and Communication technologies. This is felt in each and every section of society. Several studies have confirmed and considered information and communication technology’s significance in the field of education. It has not only affected learners but also to the teachers. This paper explores how ICT-based projects affect teachers’ and students’ attitudes. The data was collected through self-prepared attitude scale. It was distributed among the teachers and students of various schools. Two hundred students and one hundred twenty teachers responded to the questionnaire. Analysis was done through the data collected from the teachers as well as from students. The study’s conclusions demonstrated that while there was no significant variation in the attitudes of teachers utilizing different ICT-based programs, there was a substantial difference in the students’ attitude toward learning with different ICT-based programs.展开更多
As energy cooperation under the Belt and Road Initiative continues to deepen,both traditional and new energy projects require a diverse range of talents in fields such as engineering technology,management,environmenta...As energy cooperation under the Belt and Road Initiative continues to deepen,both traditional and new energy projects require a diverse range of talents in fields such as engineering technology,management,environmental protection,and finance.However,the current talent supply faces structural deficiencies,including a lack of international perspective among local talent,a shortage of interdisciplinary talents,and an inadequate framework for transnational mobility and educational cooperation,which severely constrains project implementation efficiency.展开更多
At the“Shanghai Cooperation Organization Plus”Meeting in Tianjin on September 1,Chinese President Xi Jinping announced the Global Governance Initiative(GGI)-the fourth landmark global initiative proposed in a row si...At the“Shanghai Cooperation Organization Plus”Meeting in Tianjin on September 1,Chinese President Xi Jinping announced the Global Governance Initiative(GGI)-the fourth landmark global initiative proposed in a row since 2021.The initiation of the GGI can be seen as both China’s policy response to the current international landscape and to the objective deficiencies in the existing global governance system,as well as a logical and further step in the development of China’s diplomatic theories and practices in global governance.展开更多
This paper reviews the latest advancements in artificial intelligence-assisted R&D project initiation,aiming to provide intelligent solutions for R&D management.It thoroughly examines the value of artificial i...This paper reviews the latest advancements in artificial intelligence-assisted R&D project initiation,aiming to provide intelligent solutions for R&D management.It thoroughly examines the value of artificial intelligence technologies in four core areas:intelligent requirement analysis,technical feasibility assessment,market prospect forecasting,and automated risk identification.Furthermore,it proposes three forward-looking trends—enhanced intelligence,the establishment of industry standards,and deeper human-machine collaboration.These insights are expected to improve project approval success rates and shorten initiation timelines,driving a paradigm shift in R&D management from experience-based to data-driven decision-making.The review highlights how artificial intelligence,through machine learning,natural language processing,and data mining,effectively addresses chronic challenges in traditional initiation processes such as inefficiency,delayed decisions,and resource misallocation.It also identifies critical hurdles,including data quality,model interpretability,and organizational transformation,offering a vital reference framework for the future of intelligent R&D development.展开更多
Back-arc basins are key sites for oceanic lithosphere formation and consumption at convergent plate boundaries,and their formation and subduction processes can be highly variable.The tectonic setting and evolution of ...Back-arc basins are key sites for oceanic lithosphere formation and consumption at convergent plate boundaries,and their formation and subduction processes can be highly variable.The tectonic setting and evolution of the Meso-Tethys Shiquanhe-Jiali ophiolite sub-belt(SJO sub-belt)within BangongNujiang Suture Zone(BNSZ),central xizang,are disputed for the complex rock composition and ages.In this paper,we present geochronology,geochemistry and field observations on the Shiquanhe ophiolite,providing a representative ophiolite example in the western end of SJO.Based on investigation of the petrogenesis and tectonic setting of different rock types,combined with the U-Pb dating,we propose a twostage subduction model for explaining the tectonic evolution of SJO as well as the wither away of a backarc basin.Geochemical and geochronological data indicate that the ca.183 Ma LAN(north of Lameila)gabbros formed in the forearc setting and represent the early-stage subduction of the Bangong MesoTethys.This subduction induced the back-arc spreading recorded in the ca.170 Ma gabbros and lower pillow basalts of PL-SDN(Pagelizanong-Shiquanhe Dam Nan)ophiolitic fragments in the Shiquanhe ophiolite.The basaltic lavas overlying the lower basalts,represented by the ca.168–164 Ma diabasic and boninite dikes have forearc characteristics,and they represent the back-arc basin subduction initiation at a late stage.This work thus recovered the multiple tectonic evolution of SJO sub-belt and emphasise the importance of the back-arc basin subduction in the evolution of ancient oceans.展开更多
This study analyzes 81 NHK(Japan Broadcasting Corporation)reports on the Belt and Road Initiative(BRI)from January 2020 to January 2024.It examines the changing themes,strategies,and attitudes towards the BRI.Findings...This study analyzes 81 NHK(Japan Broadcasting Corporation)reports on the Belt and Road Initiative(BRI)from January 2020 to January 2024.It examines the changing themes,strategies,and attitudes towards the BRI.Findings reveal that during the COVID-19 pandemic,NHK focused on China’s“vaccine diplomacy”and aid,portraying China as a proactive global player,while suggesting competition.In the context of the Russia-Ukraine conflict and the BRI forum,NHK’s coverage shifted towards geopolitics and international cooperation,showing skepticism and caution.Future efforts should emphasize improving communication with Japan to highlight the positive outcomes of the BRI and counter negative perceptions.展开更多
The conventional view suggests that the subduction of the South China Sea plate beneath Luzon occurred due to the oceanic lithosphere’s high density,facilitating subduction initiation.However,before the South China S...The conventional view suggests that the subduction of the South China Sea plate beneath Luzon occurred due to the oceanic lithosphere’s high density,facilitating subduction initiation.However,before the South China Sea opened,a continental margin likely existed,meaning that Luzon was directly adjacent to the continental margin rather than the oceanic basin.This would make subduction initiation more challenging.Here,we propose a new model suggesting that during the formation of the South China Sea,extensive mafic magmatic underplating occurred along its continental margin.The high-density magmatic additions may have increased the overall density of the continental margin,potentially exceeding that of Luzon,thereby enabling subduction to proceed.展开更多
The microstructure evolution and mechanical properties of a Fe-0.12C-0.2Si-1.6Mn-0.3Cr-0.0025B(wt.%)steel with different initial microstructures,i.e.,hot rolled(HR)and cold rolled-annealed(CRA),were studied through op...The microstructure evolution and mechanical properties of a Fe-0.12C-0.2Si-1.6Mn-0.3Cr-0.0025B(wt.%)steel with different initial microstructures,i.e.,hot rolled(HR)and cold rolled-annealed(CRA),were studied through optical microscopy,scanning electron microscopy,electron channeling contrast imaging,microhardness and room temperature uniaxial tensile tests.After water quenching from 930℃ to room temperature,a fully martensitic microstructure was obtained in both as-quenched HR and CRA specimens,which shows a microhardness of 480±5 HV,and no significant difference in microstructure and microhardness was observed.Tensile test results show that the product of tensile strength and total elongation(UTS×TE)of the as-quenched HR specimen,i.e.,24.1 GPa%,is higher than that of the as-quenched CRA specimen,i.e.,18.9 GPa%.While,after being tempered at 300℃,the martensitic microstructures and mechanical properties of the two as-quenched specimens change significantly due to the synergy role of the matrix phase softening and the precipitation strengthening.Concerning the maximum UTS×TE,it is 18.9 GPa%obtained in the as-quenched CRA one,while that is 24.4 GPa%obtained in the HR specimen after tempered at 300℃ for 5 min.展开更多
With a global vision and a strong sense of responsibility,the CPC has been committed to promoting exchanges and mutual learning among civilizations and advancing the progress of human civilization.In March 2023,Genera...With a global vision and a strong sense of responsibility,the CPC has been committed to promoting exchanges and mutual learning among civilizations and advancing the progress of human civilization.In March 2023,General Secretary Xi Jinping put forth the Global Civilization Initiative(GCI)at the CPC in Dialogue with World Political Parties High-level Meeting,emphasizing the need to advocate the respect for the diversity of civilizations,the common values of humanity,the importance of inheritance and innovation of civilizations,and robust international people-to-people exchanges and cooperation.展开更多
This study investigated the mediating role of basic psychological needs satisfaction in relationship between teacher support and adolescents’personal growth initiative.A total of 493 adolescents(females=44.8%,mean ag...This study investigated the mediating role of basic psychological needs satisfaction in relationship between teacher support and adolescents’personal growth initiative.A total of 493 adolescents(females=44.8%,mean age=12.46,SD=0.57)completed the Teacher Support Scale,the Adolescents’Personal Growth Initiative Scale,and the Basic Psychological Needs Scale.The results,analyzed through a Mediation model analysis results indicated higher teacher support to be significantly associated with higher adolescents’personal growth initiative.Teacher support was also associated with higher basic psychological needs satisfaction.Basic psychological needs satisfaction mediated the relationship between teacher support and adolescents’personal growth initiative for higher personal growth initiative.Thus,enhancing students’perceptions of teacher support would support the student’s sense of proactive and resilient growth with basic psychological needs satisfaction.展开更多
The Middle East has long been in turmoil,and the new round of the Palestinian-Israeli conflict has further highlighted the urgency of security governance in the region.The Global Security Initiative(GSI)proposed by Ch...The Middle East has long been in turmoil,and the new round of the Palestinian-Israeli conflict has further highlighted the urgency of security governance in the region.The Global Security Initiative(GSI)proposed by China provides theoretical guidance and practical paths for China’s participation in Middle East security governance.China’s engagement in Middle East security governance not only meets the expectations of Middle East countries but also fully demonstrates its responsibility as a major country,which is of great significance for China to explore participation in global security governance and address the global security deficit.展开更多
This study leverages machine learning to perform high-throughput computational screening of n-hexane cracking initiators.Artificial neural networks are applied to predict the chemical performance of initiators,using s...This study leverages machine learning to perform high-throughput computational screening of n-hexane cracking initiators.Artificial neural networks are applied to predict the chemical performance of initiators,using simulated pyrolysis data as the training dataset.Various feature extraction methods are utilized,and five neural network architectures are developed to predict the co-cracking product distribution based on molecular structures.High-throughput screening of 12946 molecules outside the training dataset identifies the top 10 initiators for each target product—ethylene,propylene,and butadiene.The relative error between predicted and simulated values is less than 7%.Additionally,reaction pathway analysis elucidates the mechanisms by which initiators influence the distribution of cracking products.The proposed framework provides a practical and efficient approach for the rapid identification and evaluation of high-performance cracking initiators.展开更多
Crack initiation mechanism of dwell fatigue has always been a key problem in rationalizing the dwell effect,and it is not completely understood yet.This study conducted stress-controlled low-cycle fatigue and dwell fa...Crack initiation mechanism of dwell fatigue has always been a key problem in rationalizing the dwell effect,and it is not completely understood yet.This study conducted stress-controlled low-cycle fatigue and dwell fatigue tests on Ti-6Al-3Nb-2Zr-1Mo alloy with bimodal microstructure to reveal its microstructural characteristics and crack initiation mechanisms.The study demonstrated that the faceted primaryα nodules located near the specimen surface acted as crack initiation sites during both fatigue and dwell fatigue tests.Slip trace analysis revealed that faceted cracking occurred at(0001)basal plane with the maximum Schmid factor value through a special cracking mode referred to as(0001)twist boundary cracking.Innovative criteria of parameters C1 and C2 were proposed based on experimental observation and molecular dynamics simulations,which well identify candidates for(0001)twist boundary crack nucleation.It demonstrated that grain pairs combining a moderately high Schmid factor for basal slip and a well-orientated Burgers vector in the out-of-surface plane was the preferable location for surface(0001)twist-boundary crack initiation,and grain pairs combining a high Schmid factor for basal slip and a high normal stress on basal plane are perfect candidates for subsurface cracking.Based on this,phenomeno-logical models are proposed to explain the surface(0001)twist-boundary cracking mechanism from the perspective of surface extrusion-intrusion-induced micro-notches.展开更多
In recent years,(0001)twist grain boundaries(BTGBs)located in primary α grain clusters were identified as fatigue crack nucleation sites in different Ti alloys.In the present study,crack initiation was investigated i...In recent years,(0001)twist grain boundaries(BTGBs)located in primary α grain clusters were identified as fatigue crack nucleation sites in different Ti alloys.In the present study,crack initiation was investigated in a bimodal Ti-5Al-4 V alloy subjected to low-cycle fatigue and dwell-fatigue loadings at room temperature.The low fraction of primary α grains was not associated with a lack of sensitivity to BTGB cracking.Transmission electron microscopy and electron back-scattered diffraction were used to characterize BTGBs in the initial microstructure.The fatigue mechanisms were then analyzed with a focus on dislocation activity.α_(p) grains adjacent to cracked BTGBs contained a high dislocation density.It was primarily composed of planar slip bands of dislocations.In addition,<c+a>dislocations were noticed in the vicinity of cracked BTGBs.They supposedly pertain to crack tip plasticity during growth,and no evidence of a role of an incoming slip event in crack nucleation was obtained.Also,basal slip bands extending across adjacent grains were found to emerge from BTGBs.This feature provides an easier path for crack extension when growth along the grain boundary becomes difficult owing to a deviation from the basal plane.Atom probe tomography analyses evidenced V and Fe segregation at a grain boundary with a significant deviation from the BTGB configuration.This suggests a possible contribution of local solute segregation to the high cracking resistance of general α_(p)/α_(p) grain boundaries.This work provides new insights into the mechanisms involved in cracking of BTGB in Ti alloys subjected to cyclic loadings.展开更多
文摘Recent advancements in computational and database technologies have led to the exponential growth of large-scale medical datasets,significantly increasing data complexity and dimensionality in medical diagnostics.Efficient feature selection methods are critical for improving diagnostic accuracy,reducing computational costs,and enhancing the interpretability of predictive models.Particle Swarm Optimization(PSO),a widely used metaheuristic inspired by swarm intelligence,has shown considerable promise in feature selection tasks.However,conventional PSO often suffers from premature convergence and limited exploration capabilities,particularly in high-dimensional spaces.To overcome these limitations,this study proposes an enhanced PSO framework incorporating Orthogonal Initializa-tion and a Crossover Operator(OrPSOC).Orthogonal Initialization ensures a diverse and uniformly distributed initial particle population,substantially improving the algorithm’s exploration capability.The Crossover Operator,inspired by genetic algorithms,introduces additional diversity during the search process,effectively mitigating premature convergence and enhancing global search performance.The effectiveness of OrPSOC was rigorously evaluated on three benchmark medical datasets—Colon,Leukemia,and Prostate Tumor.Comparative analyses were conducted against traditional filter-based methods,including Fast Clustering-Based Feature Selection Technique(Fast-C),Minimum Redundancy Maximum Relevance(MinRedMaxRel),and Five-Way Joint Mutual Information(FJMI),as well as prominent metaheuristic algorithms such as standard PSO,Ant Colony Optimization(ACO),Comprehensive Learning Gravitational Search Algorithm(CLGSA),and Fuzzy-Based CLGSA(FCLGSA).Experimental results demonstrated that OrPSOC consistently outperformed these existing methods in terms of classification accuracy,computational efficiency,and result stability,achieving significant improvements even with fewer selected features.Additionally,a sensitivity analysis of the crossover parameter provided valuable insights into parameter tuning and its impact on model performance.These findings highlight the superiority and robustness of the proposed OrPSOC approach for feature selection in medical diagnostic applications and underscore its potential for broader adoption in various high-dimensional,data-driven fields.
基金supported by the National Natural Science Foundation of China(Grant Nos.12474453,12174085,and 12404530).
文摘Physics-informed neural networks(PINNs)have shown considerable promise for performing numerical simulations in fluid mechanics.They provide mesh-free,end-to-end approaches by embedding physical laws into their loss functions.However,when addressing complex flow problems,PINNs still face some challenges such as activation saturation and vanishing gradients in deep network training,leading to slow convergence and insufficient prediction accuracy.We present physics-informed neural networks incorporating lattice Boltzmann method optimized by tanh robust weight initialization(T-PINN-LBM)to address these challenges.This approach fuses the mesoscopic lattice Boltzmann model with the automatic differentiation framework of PINNs.It also implements a tanh robust weight initialization method derived from fixed point analysis.This model effectively mitigates activation and gradient decay in deep networks,improving convergence speed and data efficiency in multiscale flow simulations.We validate the effectiveness of the model on the classical arithmetic example of lid-driven cavity flow.Compared to the traditional Xavier initialized PINN and PINN-LBM,T-PINNLBM reduces the mean absolute error(MAE)by one order of magnitude at the same network depth and maintains stable convergence in deeper networks.The results demonstrate that this model can accurately capture complex flow structures without prior data,providing a new feasible pathway for data-free driven fluid simulation.
基金supported by the China Scholarship Council(CSC)(No.202206290131)。
文摘This paper presents an analysis of an equilateral triangular array formation initialization for space-based gravitational wave observatory(GWO)near Lagrange points in the circular-restricted three-body problem.A stable configuration is essential for the continuous observation of gravitational waves(GWs).However,the motion near the collinear libration points is highly unstable.This problem is examined by output regulation theory.Using the tracking aspect,the equilateral triangular array formation is established in two periods and the fuel consumption is calculated.Furthermore,the natural evolution of the formation without control input is analyzed,and the effective stability duration is quantified to determine the timing of control interventions.Finally,to observe the GWs in same direction with different frequency bands,scale reconfiguration is employed.
基金supported by the National Key R&D Program of China(No.2022YFC3203602)the Natural Science Foundation of China(No.52370018)+1 种基金Shaanxi Provincial Youth Innovation Team Project(No.22JP040)Shaanxi Provincial Key Scientific and Technological Innovation Team(No.2023-CX-TD-32).
文摘During the initial impoundment period of a canyon-shaped reservoir,the water body fluctuated violently regarding water level,hydrological condition,and thermal stratification.These variations may alter the structure of phytoplankton community,resulting in algal blooms and seriously threatening the ecological security of the reservoir.It is of great significance to understand the continuous changes of phytoplankton in the initial impoundment period for the protection of reservoir water quality.Therefore,a two-year in-situ monitoring study was conducted on water quality and phytoplankton in a representative canyonshaped reservoir named Sanhekou and the interannual changes of phytoplankton community and its response to environmental changes during the initial impoundment period were discussed at taxonomic versus functional classification levels.The results showed that the total nitrogen and permanganate index levels were relatively high in the first year due to rapid water storage and heavy rainfall input,and the more stable hydrological conditions in the second year promoted the increase of algae density and the transformation of community,and the proportion of cyanobacteria increased significantly.The succession order of phytoplankton in the first year of the initial impoundment periodwas Chlorophyta-Bacillariophyta-Chlorophyta,or J/F/X1-P/MP/W1-A/X1/MP,respectively.And the succession order in the second year was Cyanobacteria/Chlorophyta-Bacillariophyta-Chlorophyta,or L_(M)/G/P-P/A/X1-X1/J/G.Water temperature,relativewater column stability,mixing depth,and pHwere crucial factors affecting phytoplankton community succession.This study revealed the interannual succession law and driving factors of phytoplankton in the initial impoundment period and provided an important reference for the operation management and ecological protection of canyon-shaped reservoirs.
文摘Evaluation of hydromechanical shear behavior of unsaturated soils is still a challenging issue. The time and cost needed for conducting precise experimental investigation on shear behavior of unsaturated soils have encouraged several investigators to develop analytical, empirical, or semi-empirical models for predicting the shear behavior of unsaturated soils. However, most of the previously proposed models are for specimens subjected to the isotropic state of stress, without considering the effect of initial shear stress. In this study, a hydromechanical constitutive model is proposed for unsaturated collapsible soils during shearing, with consideration of the effect of the initial shear stress. The model implements an effective stress-based disturbed state concept (DSC) to predict the stress-strain behavior of the soil. Accordingly, material/state variables were defined for both the start of the shearing stage and the critical state of the soil. A series of laboratory tests was performed using a fully automated unsaturated triaxial device to verify the proposed model. The experimental program included 23 suction-controlled unsaturated triaxial shear tests on reconstituted specimens of Gorgan clayey loess wetted to different levels of suctions under both isotropic and anisotropic stress states. The results show excellent agreement between the prediction by the proposed model and the experimental results.
文摘We study the two-dimensional(2D)Cauchy problem of nonhomogeneous Boussinesq system for magnetohydrodynamics convection without heat diffusion in the whole plane.Based on delicate weighted estimates,we derive the global existence and uniqueness of strong solutions.In particular,the initial data can be arbitrarily large and the initial density may contain vacuum states and even have compact support.
文摘There is curiosity and awareness throughout the world regarding the role of Information and Communication technologies. This is felt in each and every section of society. Several studies have confirmed and considered information and communication technology’s significance in the field of education. It has not only affected learners but also to the teachers. This paper explores how ICT-based projects affect teachers’ and students’ attitudes. The data was collected through self-prepared attitude scale. It was distributed among the teachers and students of various schools. Two hundred students and one hundred twenty teachers responded to the questionnaire. Analysis was done through the data collected from the teachers as well as from students. The study’s conclusions demonstrated that while there was no significant variation in the attitudes of teachers utilizing different ICT-based programs, there was a substantial difference in the students’ attitude toward learning with different ICT-based programs.
基金2024 Western Project of the National Social Science Fund,"Research on Promotion Strategies and Implementation Paths for High-Quality Energy Cooperation under the Belt and Road Initiative"(No.24XGJ002)PetroChina Southwest Oil&Gasfield Company Scientific Research Project,"Research on the Construction of Professional Technical Talent Teams in the PetroChina Southwest Oil&Gasfield Company"(No.2024D111-01-03)Chengdu soft science research project titled"Research on the Path to Achieve High-quality Clean Energy Cooperation between Chengdu and Countries along the Belt and Road"(No.2025-RK00-00088-ZF).
文摘As energy cooperation under the Belt and Road Initiative continues to deepen,both traditional and new energy projects require a diverse range of talents in fields such as engineering technology,management,environmental protection,and finance.However,the current talent supply faces structural deficiencies,including a lack of international perspective among local talent,a shortage of interdisciplinary talents,and an inadequate framework for transnational mobility and educational cooperation,which severely constrains project implementation efficiency.
文摘At the“Shanghai Cooperation Organization Plus”Meeting in Tianjin on September 1,Chinese President Xi Jinping announced the Global Governance Initiative(GGI)-the fourth landmark global initiative proposed in a row since 2021.The initiation of the GGI can be seen as both China’s policy response to the current international landscape and to the objective deficiencies in the existing global governance system,as well as a logical and further step in the development of China’s diplomatic theories and practices in global governance.
文摘This paper reviews the latest advancements in artificial intelligence-assisted R&D project initiation,aiming to provide intelligent solutions for R&D management.It thoroughly examines the value of artificial intelligence technologies in four core areas:intelligent requirement analysis,technical feasibility assessment,market prospect forecasting,and automated risk identification.Furthermore,it proposes three forward-looking trends—enhanced intelligence,the establishment of industry standards,and deeper human-machine collaboration.These insights are expected to improve project approval success rates and shorten initiation timelines,driving a paradigm shift in R&D management from experience-based to data-driven decision-making.The review highlights how artificial intelligence,through machine learning,natural language processing,and data mining,effectively addresses chronic challenges in traditional initiation processes such as inefficiency,delayed decisions,and resource misallocation.It also identifies critical hurdles,including data quality,model interpretability,and organizational transformation,offering a vital reference framework for the future of intelligent R&D development.
基金supported by the Guangdong Basic and Applied Basic Research Foundation,China(Grant Nos.2024A1515010439,2025A1515010724)National Nature Science Foundation of China(Grant Nos.41972049,41472054,42072229,41977231)+4 种基金Young Innovative Talent Project of Department of Education of Guangdong Province(Natural ScienceGrant No.2022KQNCX184)Natural Research Project of Guangdong Polytechnic of Industry&Commerce(Grant No.2022-ZKT-01)China State Scholarship Fund of visiting scholar(Grant No.20170638507)High-level Talent Special Support Program of Guangdong Polytechnic of Industry&Commerce(Grant No.2023-gc-03).
文摘Back-arc basins are key sites for oceanic lithosphere formation and consumption at convergent plate boundaries,and their formation and subduction processes can be highly variable.The tectonic setting and evolution of the Meso-Tethys Shiquanhe-Jiali ophiolite sub-belt(SJO sub-belt)within BangongNujiang Suture Zone(BNSZ),central xizang,are disputed for the complex rock composition and ages.In this paper,we present geochronology,geochemistry and field observations on the Shiquanhe ophiolite,providing a representative ophiolite example in the western end of SJO.Based on investigation of the petrogenesis and tectonic setting of different rock types,combined with the U-Pb dating,we propose a twostage subduction model for explaining the tectonic evolution of SJO as well as the wither away of a backarc basin.Geochemical and geochronological data indicate that the ca.183 Ma LAN(north of Lameila)gabbros formed in the forearc setting and represent the early-stage subduction of the Bangong MesoTethys.This subduction induced the back-arc spreading recorded in the ca.170 Ma gabbros and lower pillow basalts of PL-SDN(Pagelizanong-Shiquanhe Dam Nan)ophiolitic fragments in the Shiquanhe ophiolite.The basaltic lavas overlying the lower basalts,represented by the ca.168–164 Ma diabasic and boninite dikes have forearc characteristics,and they represent the back-arc basin subduction initiation at a late stage.This work thus recovered the multiple tectonic evolution of SJO sub-belt and emphasise the importance of the back-arc basin subduction in the evolution of ancient oceans.
基金supported by the Nanjing University of Finance and Economics Teaching Reform Project,“Exploration and Practice of Ideological and Political Education in Elementary Japanese Courses:A Multidimensional Integration from Language Origins to Social Issues”(Project Number:XJWC3202449).
文摘This study analyzes 81 NHK(Japan Broadcasting Corporation)reports on the Belt and Road Initiative(BRI)from January 2020 to January 2024.It examines the changing themes,strategies,and attitudes towards the BRI.Findings reveal that during the COVID-19 pandemic,NHK focused on China’s“vaccine diplomacy”and aid,portraying China as a proactive global player,while suggesting competition.In the context of the Russia-Ukraine conflict and the BRI forum,NHK’s coverage shifted towards geopolitics and international cooperation,showing skepticism and caution.Future efforts should emphasize improving communication with Japan to highlight the positive outcomes of the BRI and counter negative perceptions.
基金support from the National Natural Science Foundation of China (Grant No. 42276049)。
文摘The conventional view suggests that the subduction of the South China Sea plate beneath Luzon occurred due to the oceanic lithosphere’s high density,facilitating subduction initiation.However,before the South China Sea opened,a continental margin likely existed,meaning that Luzon was directly adjacent to the continental margin rather than the oceanic basin.This would make subduction initiation more challenging.Here,we propose a new model suggesting that during the formation of the South China Sea,extensive mafic magmatic underplating occurred along its continental margin.The high-density magmatic additions may have increased the overall density of the continental margin,potentially exceeding that of Luzon,thereby enabling subduction to proceed.
基金Chongqing Natural Science Foundation(No.CSTB2022NSCQ-MSX1394)Graduate Research and Innovation Foundation of Chongqing,China(Grant No.CYS22008)+2 种基金Open Project of State Key Laboratory of Advanced Special Steel,Shanghai Key Laboratory of Advanced Ferrometallurgy,Shanghai University(SKLASS 2023-10)the Science and Technology Commission of Shanghai Municipality(No.19DZ2270200)the Open Project of the Large Casting and Forging Manufacturing Technology Engineering Center of Shanghai Institute of Mechanical and Electrical Engineering,State Key Laboratory of Vanadium and Titanium Resources Open Fund(No.2022P4FZG04A).
文摘The microstructure evolution and mechanical properties of a Fe-0.12C-0.2Si-1.6Mn-0.3Cr-0.0025B(wt.%)steel with different initial microstructures,i.e.,hot rolled(HR)and cold rolled-annealed(CRA),were studied through optical microscopy,scanning electron microscopy,electron channeling contrast imaging,microhardness and room temperature uniaxial tensile tests.After water quenching from 930℃ to room temperature,a fully martensitic microstructure was obtained in both as-quenched HR and CRA specimens,which shows a microhardness of 480±5 HV,and no significant difference in microstructure and microhardness was observed.Tensile test results show that the product of tensile strength and total elongation(UTS×TE)of the as-quenched HR specimen,i.e.,24.1 GPa%,is higher than that of the as-quenched CRA specimen,i.e.,18.9 GPa%.While,after being tempered at 300℃,the martensitic microstructures and mechanical properties of the two as-quenched specimens change significantly due to the synergy role of the matrix phase softening and the precipitation strengthening.Concerning the maximum UTS×TE,it is 18.9 GPa%obtained in the as-quenched CRA one,while that is 24.4 GPa%obtained in the HR specimen after tempered at 300℃ for 5 min.
文摘With a global vision and a strong sense of responsibility,the CPC has been committed to promoting exchanges and mutual learning among civilizations and advancing the progress of human civilization.In March 2023,General Secretary Xi Jinping put forth the Global Civilization Initiative(GCI)at the CPC in Dialogue with World Political Parties High-level Meeting,emphasizing the need to advocate the respect for the diversity of civilizations,the common values of humanity,the importance of inheritance and innovation of civilizations,and robust international people-to-people exchanges and cooperation.
文摘This study investigated the mediating role of basic psychological needs satisfaction in relationship between teacher support and adolescents’personal growth initiative.A total of 493 adolescents(females=44.8%,mean age=12.46,SD=0.57)completed the Teacher Support Scale,the Adolescents’Personal Growth Initiative Scale,and the Basic Psychological Needs Scale.The results,analyzed through a Mediation model analysis results indicated higher teacher support to be significantly associated with higher adolescents’personal growth initiative.Teacher support was also associated with higher basic psychological needs satisfaction.Basic psychological needs satisfaction mediated the relationship between teacher support and adolescents’personal growth initiative for higher personal growth initiative.Thus,enhancing students’perceptions of teacher support would support the student’s sense of proactive and resilient growth with basic psychological needs satisfaction.
文摘The Middle East has long been in turmoil,and the new round of the Palestinian-Israeli conflict has further highlighted the urgency of security governance in the region.The Global Security Initiative(GSI)proposed by China provides theoretical guidance and practical paths for China’s participation in Middle East security governance.China’s engagement in Middle East security governance not only meets the expectations of Middle East countries but also fully demonstrates its responsibility as a major country,which is of great significance for China to explore participation in global security governance and address the global security deficit.
基金The financial support provided by the Project of the National Natural Science Foundation of China (22308314,U22A20415)the Natural Science Foundation of Zhejiang Province (LQ24B060001)+1 种基金the "Pioneer" and "Leading Goose" Research & Development Program of Zhejiang (2022C01SA442617)the SINOPEC Technology Development Project (224244)
文摘This study leverages machine learning to perform high-throughput computational screening of n-hexane cracking initiators.Artificial neural networks are applied to predict the chemical performance of initiators,using simulated pyrolysis data as the training dataset.Various feature extraction methods are utilized,and five neural network architectures are developed to predict the co-cracking product distribution based on molecular structures.High-throughput screening of 12946 molecules outside the training dataset identifies the top 10 initiators for each target product—ethylene,propylene,and butadiene.The relative error between predicted and simulated values is less than 7%.Additionally,reaction pathway analysis elucidates the mechanisms by which initiators influence the distribution of cracking products.The proposed framework provides a practical and efficient approach for the rapid identification and evaluation of high-performance cracking initiators.
基金supported by the National Natural Science Foundation of China(Nos.52074231,52274396 and 52001258)the Chongqing Natural Science Foundation(No.cstc2020jcyj-msxmX1056).
文摘Crack initiation mechanism of dwell fatigue has always been a key problem in rationalizing the dwell effect,and it is not completely understood yet.This study conducted stress-controlled low-cycle fatigue and dwell fatigue tests on Ti-6Al-3Nb-2Zr-1Mo alloy with bimodal microstructure to reveal its microstructural characteristics and crack initiation mechanisms.The study demonstrated that the faceted primaryα nodules located near the specimen surface acted as crack initiation sites during both fatigue and dwell fatigue tests.Slip trace analysis revealed that faceted cracking occurred at(0001)basal plane with the maximum Schmid factor value through a special cracking mode referred to as(0001)twist boundary cracking.Innovative criteria of parameters C1 and C2 were proposed based on experimental observation and molecular dynamics simulations,which well identify candidates for(0001)twist boundary crack nucleation.It demonstrated that grain pairs combining a moderately high Schmid factor for basal slip and a well-orientated Burgers vector in the out-of-surface plane was the preferable location for surface(0001)twist-boundary crack initiation,and grain pairs combining a high Schmid factor for basal slip and a high normal stress on basal plane are perfect candidates for subsurface cracking.Based on this,phenomeno-logical models are proposed to explain the surface(0001)twist-boundary cracking mechanism from the perspective of surface extrusion-intrusion-induced micro-notches.
基金financially supported by the National Natural Science Foundation of China(No.U21A2050)support of the Chinese Scholarship Council(No.202006290165).
文摘In recent years,(0001)twist grain boundaries(BTGBs)located in primary α grain clusters were identified as fatigue crack nucleation sites in different Ti alloys.In the present study,crack initiation was investigated in a bimodal Ti-5Al-4 V alloy subjected to low-cycle fatigue and dwell-fatigue loadings at room temperature.The low fraction of primary α grains was not associated with a lack of sensitivity to BTGB cracking.Transmission electron microscopy and electron back-scattered diffraction were used to characterize BTGBs in the initial microstructure.The fatigue mechanisms were then analyzed with a focus on dislocation activity.α_(p) grains adjacent to cracked BTGBs contained a high dislocation density.It was primarily composed of planar slip bands of dislocations.In addition,<c+a>dislocations were noticed in the vicinity of cracked BTGBs.They supposedly pertain to crack tip plasticity during growth,and no evidence of a role of an incoming slip event in crack nucleation was obtained.Also,basal slip bands extending across adjacent grains were found to emerge from BTGBs.This feature provides an easier path for crack extension when growth along the grain boundary becomes difficult owing to a deviation from the basal plane.Atom probe tomography analyses evidenced V and Fe segregation at a grain boundary with a significant deviation from the BTGB configuration.This suggests a possible contribution of local solute segregation to the high cracking resistance of general α_(p)/α_(p) grain boundaries.This work provides new insights into the mechanisms involved in cracking of BTGB in Ti alloys subjected to cyclic loadings.
