The two-dimensional Rayleigh-Taylor Instability(RTI)under multi-mode perturbation in compressible flow is probed via the Discrete Boltzmann Modeling(DBM)with tracers.The distribution of tracers provides clear boundari...The two-dimensional Rayleigh-Taylor Instability(RTI)under multi-mode perturbation in compressible flow is probed via the Discrete Boltzmann Modeling(DBM)with tracers.The distribution of tracers provides clear boundaries between light and heavy fluids in the position space.Besides,the position-velocity phase space offers a new perspective for understanding the flow behavior of RTI with intuitive geometrical correspondence.The effects of viscosity,acceleration,compressibility,and Atwood number on the mixing of material and momentum and the mean nonequilibrium strength at the interfaces are investigated separately based on both the mixedness defined by the tracers and the non-equilibrium strength defined by the DBM.The mixedness increases with viscosity during early stage but decreases with viscosity at the later stage.Acceleration,compressibility,and Atwood number show enhancement effects on mixing based on different mechanisms.After the system relaxes from the initial state,the mean non-equilibrium strength at the interfaces presents an initially increasing and then declining trend,which is jointly determined by the interface length and the macroscopic physical quantity gradient.We conclude that the four factors investigated all significantly affect early evolution behavior of an RTI system,such as the competition between interface length and macroscopic physical quantity gradient.The results contribute to the understanding of the multi-mode RTI evolutionary mechanism and the accompanied kinetic effects.展开更多
Cancer continues to be a major public health issue worldwide.Given the complexity of the etiology and pathophysiology of cancer,challenges always exist at every step of cancer management,including early screening,diag...Cancer continues to be a major public health issue worldwide.Given the complexity of the etiology and pathophysiology of cancer,challenges always exist at every step of cancer management,including early screening,diagnosis,treatment selection,and surveillance.Emerging novel technologies hold promise in addressing a wide range of healthcare problems.Artificial intelligence(AI),which is capable of learning of features from given datasets.展开更多
The corrosion problems of high-voltage power transmission conductors typically occur in environments with electric fields.However,current research mainly focuses on atmospheric corrosion of metals with limited attenti...The corrosion problems of high-voltage power transmission conductors typically occur in environments with electric fields.However,current research mainly focuses on atmospheric corrosion of metals with limited attention to the combined effects of electric fields and atmospheric conditions on metal corrosion.This study established a corrosion prediction model that considers the effects of electric fields and dynamic boundaries.Because of the influence of dynamic boundaries,this model can calculate parameters such as corrosion rate,corrosion depth,corrosion product accumulation and ion concentration for metal samples with and without an external electric field.The model is validated through indoor accelerated corrosion tests under low applied electric fields and by using aluminium alloy conductor samples from high electric field regions of actual±500 kV power transmission lines.The results indicate that the corrosion rate of aluminium alloys initially increases and then decreases over time.Additionally,the corrosion rate of aluminium alloys under an applied electric field is higher than that without an electric field during the same period.The mechanism of increased corrosion rate is analysed to be that the presence of the electric field accelerates the cathode reaction rate of the electrode.The corrosion rate of the sample increased by about 78%under a lower electric field(0-20 kV/m)and by about 2.75 times under a higher electric field around 2000 kV/m.展开更多
It has been recognized that international students studying in non-Anglophone countries face more challenges in integrating into local higher education institutions for a number of reasons,such as the local language b...It has been recognized that international students studying in non-Anglophone countries face more challenges in integrating into local higher education institutions for a number of reasons,such as the local language barrier and cultural differences.This study aims to understand the challenges and coping strategies of academic integration in non-Anglophone countries from the students’perceptive,taking Chinese students as an example and using a qualitative approach based on semi-structured interviews with 58 Chinese students in Germany and Finland.It shows that,despite learning environment differences between Finland and Germany,Chinese students face similar challenges,including individual ones,such as the mismatch between their academic background and learning requirements,or contextual ones,such as a lack of consideration for international students in the pedagogical approach and curriculum design adopted by the host higher education institutions.The results challenge the existing stereotype of Chinese students and present evidence of students’resourcefulness in generating novel approaches to develop their learning capabilities.It also shows that traditional learning techniques may be used as pathways to achieving deep learning and understanding.展开更多
基金supported by the National Natural Science Foundation of China(under Grant No.12172061)the Opening Project of State Key Laboratory of Explosion Science and Technology(Beijing Institute of Technology)under Grant No.KFJJ21-16 MFoundation of Laboratory of Computational Physics。
文摘The two-dimensional Rayleigh-Taylor Instability(RTI)under multi-mode perturbation in compressible flow is probed via the Discrete Boltzmann Modeling(DBM)with tracers.The distribution of tracers provides clear boundaries between light and heavy fluids in the position space.Besides,the position-velocity phase space offers a new perspective for understanding the flow behavior of RTI with intuitive geometrical correspondence.The effects of viscosity,acceleration,compressibility,and Atwood number on the mixing of material and momentum and the mean nonequilibrium strength at the interfaces are investigated separately based on both the mixedness defined by the tracers and the non-equilibrium strength defined by the DBM.The mixedness increases with viscosity during early stage but decreases with viscosity at the later stage.Acceleration,compressibility,and Atwood number show enhancement effects on mixing based on different mechanisms.After the system relaxes from the initial state,the mean non-equilibrium strength at the interfaces presents an initially increasing and then declining trend,which is jointly determined by the interface length and the macroscopic physical quantity gradient.We conclude that the four factors investigated all significantly affect early evolution behavior of an RTI system,such as the competition between interface length and macroscopic physical quantity gradient.The results contribute to the understanding of the multi-mode RTI evolutionary mechanism and the accompanied kinetic effects.
基金supported by grants from the National Key Research and Development Program of China(2016YFC1302300)the National Natural Science Foundation of China(81621004,81720108029,81930081,91940305)+5 种基金Guangdong Science and Technology Department(2020B1212060018,2020B1212030004)Clinical Innovation Research Program of Bioland Laboratory(2018GZR0201004)Guangzhou Science Technology and Innovation Commission(201803040015)the Program for Guangdong Introducing Innovative and Enterpreneurial Teams(2019BT02Y198)partly supported by Fountain-Valley Life Sciences Fund of University of Chinese Academy of Sciences Education Foundationsupported by the Sun Yat-Sen University Clinical Research 5010 Program(#2018022)。
文摘Cancer continues to be a major public health issue worldwide.Given the complexity of the etiology and pathophysiology of cancer,challenges always exist at every step of cancer management,including early screening,diagnosis,treatment selection,and surveillance.Emerging novel technologies hold promise in addressing a wide range of healthcare problems.Artificial intelligence(AI),which is capable of learning of features from given datasets.
基金supported by National Key Research and Development Program of China,Grant/Award Number:2024YFB4206900.
文摘The corrosion problems of high-voltage power transmission conductors typically occur in environments with electric fields.However,current research mainly focuses on atmospheric corrosion of metals with limited attention to the combined effects of electric fields and atmospheric conditions on metal corrosion.This study established a corrosion prediction model that considers the effects of electric fields and dynamic boundaries.Because of the influence of dynamic boundaries,this model can calculate parameters such as corrosion rate,corrosion depth,corrosion product accumulation and ion concentration for metal samples with and without an external electric field.The model is validated through indoor accelerated corrosion tests under low applied electric fields and by using aluminium alloy conductor samples from high electric field regions of actual±500 kV power transmission lines.The results indicate that the corrosion rate of aluminium alloys initially increases and then decreases over time.Additionally,the corrosion rate of aluminium alloys under an applied electric field is higher than that without an electric field during the same period.The mechanism of increased corrosion rate is analysed to be that the presence of the electric field accelerates the cathode reaction rate of the electrode.The corrosion rate of the sample increased by about 78%under a lower electric field(0-20 kV/m)and by about 2.75 times under a higher electric field around 2000 kV/m.
文摘It has been recognized that international students studying in non-Anglophone countries face more challenges in integrating into local higher education institutions for a number of reasons,such as the local language barrier and cultural differences.This study aims to understand the challenges and coping strategies of academic integration in non-Anglophone countries from the students’perceptive,taking Chinese students as an example and using a qualitative approach based on semi-structured interviews with 58 Chinese students in Germany and Finland.It shows that,despite learning environment differences between Finland and Germany,Chinese students face similar challenges,including individual ones,such as the mismatch between their academic background and learning requirements,or contextual ones,such as a lack of consideration for international students in the pedagogical approach and curriculum design adopted by the host higher education institutions.The results challenge the existing stereotype of Chinese students and present evidence of students’resourcefulness in generating novel approaches to develop their learning capabilities.It also shows that traditional learning techniques may be used as pathways to achieving deep learning and understanding.
