Based on the dynamics of ABS-equipped vehicles during cornering braking, the electronic brake- force distribution (EBD) control methods of ABS-equipped vehicles during cornering braking are proposed. According to th...Based on the dynamics of ABS-equipped vehicles during cornering braking, the electronic brake- force distribution (EBD) control methods of ABS-equipped vehicles during cornering braking are proposed. According to the dynamics and the tire model under tire adhesion limit, the stability acceptance criteria of vehicles during cornering braking are proposed. According to the stability acceptance criteria and the ABS control, the EBD control methods of ABS-equipped vehicles during cornering braking are implemented by adjusting the threshold values of tires slip independently. The vehicle states during cornering braking at two typical initial velocities of the vehicle are analyzed by the EBD control methods, whose results indicate the EBD control methods can improve the braking performances of the vehicle during cornering braking comparing with the ABS control.展开更多
Mechanical elastic wheel(ME-wheel)is a new type of non-inflatable safety tyre,and the structure is significantly different from traditional pneumatic tyre.In order to investigate cornering properties of ME-wheel,exper...Mechanical elastic wheel(ME-wheel)is a new type of non-inflatable safety tyre,and the structure is significantly different from traditional pneumatic tyre.In order to investigate cornering properties of ME-wheel,experimental research on mechanics characteristics of ME-wheel under steady-state cornering conditions are carried out.The test of steady-state cornering properties of ME-wheel at different experimental parameter conditions is conducted by test bench for dynamic mechanical properties of tyre.Cornering property curves are used to analyze the steady-state cornering properties of ME-wheel,namely the variation tendency of lateral force or aligning torque with the increase of side-slip angle.Moreover,evaluation indexes for cornering properties of ME-wheel are extracted and the effect of different experimental parameters(including vertical load,friction coefficient,and speed)on cornering properties of ME-wheel is contrastively analyzed.The proposed research can provide certain reference to facilitate structure parameters and cornering properties optimizing process of ME-wheel.展开更多
To improve the handling performance of a steer-by-wire (SBW) vehicle, a series of control logics are proposed. Firstly, an algorithm for enhancing the maneuvering in steady-state cornering is presented. On this basis,...To improve the handling performance of a steer-by-wire (SBW) vehicle, a series of control logics are proposed. Firstly, an algorithm for enhancing the maneuvering in steady-state cornering is presented. On this basis, two categories of control strategies are used to dynamically correct and compensate the transient state steering responses and vehicle behaviors. Simulator tests including subjective evaluations and virtual field tests are both conducted to make comprehensive investigations on the series of control logics. The subjective evaluations demonstrate that the SBW vehicle with a specifically selected value of steering sensitivity tends to be more desirable for driving than a conventional one in which a fixed steering ratio exists. The virtual field tests indicate that the control strategies for dynamical correction and compensation could effectively improve the handling per-formances of an SBW vehicle by reducing the work load of drivers, enhancing the track-holding performance, and improving steering response properties.展开更多
Although electric vehicle fully exhibits its comparative merits of energy conservation and environmental friendliness, further improvement of its traction energy efficiency lacks comprehensive investigations in the pa...Although electric vehicle fully exhibits its comparative merits of energy conservation and environmental friendliness, further improvement of its traction energy efficiency lacks comprehensive investigations in the past. In this paper, the effect of the torque vectoring on traction energy conservation during cornering for a rear-wheel-independent-drive electric vehicle is investigated.Firstly, turning resistance coefficient and energy conservation mechanism of torque vectoring are derived from the single track dynamic model. Next, an optimal torque vectoring control strategy based on genetic algorithm is proposed, with the consideration of the influence of the operation-point change of the in-wheel motors, to find out the best torque vectoring ratio offline. Finally,various simulation tests are conducted to validate the energy conservation effect after Simulink modelling. The results verify that though the optimization of the operating region of the motors is the main part for tractive energy conservation, the contribution of torque vectoring itself can reach up to 1.7% in some typical cases.展开更多
Dear colleagues,authors,reviewers,and readers,As we bid farewell to another remarkable year,I am filled with immense gratitude and pride for the strides we have made together in advancing the field of neural regenerat...Dear colleagues,authors,reviewers,and readers,As we bid farewell to another remarkable year,I am filled with immense gratitude and pride for the strides we have made together in advancing the field of neural regeneration.On behalf of Neural Regeneration Research(NRR),I extend my heartfelt thanks to our dedicated editorial board members,reviewers,authors,readers,and the NRR staff.Your unwavering commitment and support have been the cornerstone of our success,and without your contributions,the journal would not have achieved the milestones we celebrate today.展开更多
Four-Wheel Independent Steering(4WIS)Vehicles can independently control the angle of each wheel,demonstrating superior trajectory tracking performance under normal conditions.However,on intermittent icy and snowy road...Four-Wheel Independent Steering(4WIS)Vehicles can independently control the angle of each wheel,demonstrating superior trajectory tracking performance under normal conditions.However,on intermittent icy and snowy roads,the presence of time-varying adhesion coefficients,time-varying cornering stiffness,and the irregularities due to ice and snow accumulation introduce multiple uncertainties into the steering system,significantly degrading the trajectory tracking performance of 4WIS vehicles.In response,this paper proposes a robust Tube Model Predictive Control(Tube-MPC)trajectory tracking control method for 4WIS.In this method,a Bi-directional Long Short-Term Memory neural network is established for online estimation of tire cornering stiffness under different road adhesion coefficients,providing accurate estimation of time-varying cornering stiffness for each wheel to mitigate the uncertainties of time-varying adhesion coefficients and cornering stiffness.Additionally,considering the road irregularities caused by snow accumulation on intermittent icy and snowy roads,a trajectory tracking controller that integrates Tube-MPC and robust Sliding Mode Control is proposed.The nominal MPC model,developed from the estimated tire cornering stiffness,utilizes the sliding surface and the optimal auxiliary control unit law for the tube is derived from the reaching law in Tube-MPC,aiming to minimize the trajectory tracking error while enhancing the controller’s robustness against road uncertainties.The experiments show that the proposed method outperforms the Tube-MPC algorithm in terms of trajectory accuracy and robustness.This method demonstrates excellent trajectory tracking accuracy under intermittent icy and snowy road conditions,and it lays a theoretical foundation for future studies on vehicle stability and trajectory tracking under such road conditions.展开更多
Higher-order band topology not only enriches our understanding of topological phases but also unveils pioneering lower-dimensional boundary states,which harbors substantial potential for next-generation device applica...Higher-order band topology not only enriches our understanding of topological phases but also unveils pioneering lower-dimensional boundary states,which harbors substantial potential for next-generation device applications.The distinct electronic configurations and tunable attributes of two-dimensional materials position them as a quintessential platform for the realization of second-order topological insulators(SOTIs).This article provides an overview of the research progress in SOTIs within the field of two-dimensional electronic materials,focusing on the characterization of higher-order topological properties and the numerous candidate materials proposed in theoretical studies.These endeavors not only enhance our understanding of higher-order topological states but also highlight potential material systems that could be experimentally realized.展开更多
Currently,the design of advanced compressor blades has reached the full ThreeDimensional(3D)modeling stage.When analyzing the reasons for the failure of popular corner stall prediction criteria for axial compressors t...Currently,the design of advanced compressor blades has reached the full ThreeDimensional(3D)modeling stage.When analyzing the reasons for the failure of popular corner stall prediction criteria for axial compressors to predict the corner flow state in modern compressor3D blades with end-bend and composite bend-sweep characteristics,it is believed that,in addition to the dihedral angle factor in the corner,the variation of the dihedral angle along the flow path is an important factor that has not been considered to date.In light of this,this study first uses the characteristic effects of the diffuser on the deceleration and pressure increase in airflow to design a series of physical models of varying dihedral angle diffusers that are equivalent to compressors.Based on these models,a quantization parameter is established to characterize the development speed of the intersection of boundary layers at the corner under varying dihedral angle and adverse pressure gradient conditions.After combining this with the effects of secondary flow,a Modified diffusion factor DJ(MDJ)is developed to describe the development of corner flow from the leading edge of the blade to its trailing edge under varying dihedral angle conditions.Finally,based on a compressor cascade database,an improved criterion for predicting corner stall in axial compressors using the MDJ diffusion factor is proposed.The validation results,based on extensive experimental data of compressor blades,reveal that this improved criterion can significantly enhance the accuracy of corner stall predictions in the 3D blades of modern compressors compared to currently used prediction criteria,by taking into account the effects of variations in the dihedral angle.展开更多
To understand the specific behaviors of coastal coral sand slope foundations,discrete element method(DEM)was employed to examine the effect of breakable particle corners on the performance of coral sand slope foundati...To understand the specific behaviors of coastal coral sand slope foundations,discrete element method(DEM)was employed to examine the effect of breakable particle corners on the performance of coral sand slope foundations under a strip footing,from macro to micro scales.The results demonstrate that the bearing characteristics of coral sand slope foundations can be successfully modeled by utilizing breakable corner particles in simulations.The dual effects of interlocking and breakage of corners well explained the specific shallower load transmission and narrower shear stress zones in breakable corner particle slopes.Additionally,the study revealed the significant influence of breakable corners on soil behaviors on slopes.Furthermore,progressive corner breakage within slip bands was successfully identified as the underling mechanism in determining the unique bearing characteristics and the distinct failure patterns of breakable corner particle slopes.This study provides a new perspective to clarify the behaviors of slope foundations composed of breakable corner particle materials.展开更多
Topological insulators represent a new phase of matter,characterized by conductive surfaces,while their bulk remains insulating.When the dimension of the system exceeds that of the topological state by at least two,th...Topological insulators represent a new phase of matter,characterized by conductive surfaces,while their bulk remains insulating.When the dimension of the system exceeds that of the topological state by at least two,the insulators are classified as higher-order topological insulators(HOTI).The appearance of higher-order topological states,such as corner states,can be explained by the filling anomaly,which leads to the fractional spectral charges in the unit cell.Previously reported fractional charges have been quite limited in number and size.In this work,based on the two-dimensional(2D)Su-Schrieffer-Heeger model lattice,we demonstrated a new class of HOTIs with adjustable fractional charges that can take any value ranging from 0 to 1,achieved by utilizing the Lorentz transformation.Furthermore,this transformation generates novel bound-state-in-continuum-like corner states,even when the lattice is in a topological trivial phase,offering a new approach to light beam localization.This work paves the way for fabricating HOTIs with diverse corner states that offer promising applicative potential.展开更多
Governing technology with technology will be a cornerstone of intelligent communication in the AI era.WITH the rapid development of information technology,the media industry is undergoing unprecedented changes.It has ...Governing technology with technology will be a cornerstone of intelligent communication in the AI era.WITH the rapid development of information technology,the media industry is undergoing unprecedented changes.It has evolved from Internet-based communication and communication on social media platforms to intelligent communication.The revolution of science and technology has always been a core force driving changes in the media.展开更多
Investment remains a cornerstone of China’s economic resilience amid global headwinds and structural transitions.In the short term,it drives sectoral growth,creates jobs,and stabilizes economic momentum.Over the long...Investment remains a cornerstone of China’s economic resilience amid global headwinds and structural transitions.In the short term,it drives sectoral growth,creates jobs,and stabilizes economic momentum.Over the long term,a well-structured investment allocation fuels industrial innovation and upgrading,laying a solid foundation for sustainable economic development.展开更多
Mutual learning is a cornerstone for building a global community of shared future.Cultural Envoys:Connecting Civilizations introduces the winners of the Orchid Awards,a recent laurel instituted by the China Internatio...Mutual learning is a cornerstone for building a global community of shared future.Cultural Envoys:Connecting Civilizations introduces the winners of the Orchid Awards,a recent laurel instituted by the China International Communications Group to recognize the work of people worldwide who have made significant contributions to cultural exchanges and mutual learning between China and the rest of the world.展开更多
As human society progresses,it faces a range of complex and unprecedented challenges.These include the global energy crisis,environmental degradation,antibiotic resistance,an aging population,and the rapid rise of art...As human society progresses,it faces a range of complex and unprecedented challenges.These include the global energy crisis,environmental degradation,antibiotic resistance,an aging population,and the rapid rise of artificial intelligence(AI).Addressing these issues demands innovative solutions.Historically,scientific discovery has been the cornerstone for overcoming such challenges and driving sustainable development.Yet,as research continues to evolve,achieving breakthroughs that fundamentally shift paradigms-those that take us from"0-1"-is becoming increasingly difficult.One source of untapped innovation lies in nature,a profound teacher from which humans have drawn inspiration for millennia.Through evolution,various species have developed extraordinary strategies to survive and adapt to their environments.This accumulated wisdom offers invaluable insights for advancing science and technology.For instance,the adaptive color change of the chameleon allows it to camouflage,communicate,and regulate its body temperature.Similarly,the electric eel has evolved specialized cells that produce powerful electric currents for defense and hunting.The collective behavior of bees,where individuals follow simple rules to achieve complex group functions,has inspired the development of distributed systems in robotics and AI.Additionally,the nanostructure of cicada wings,which display outstanding optical control and microbial resistance,has informed cutting-edge innovations in materials science,rivaling even the most advanced human technologies.展开更多
Farmer Luo Baozhen receives regular weather updates on her smartphone,which help her to better manage her tea farm.Once living in precarious conditions and struggling to make ends meet,Luo now earns as much as 28,000 ...Farmer Luo Baozhen receives regular weather updates on her smartphone,which help her to better manage her tea farm.Once living in precarious conditions and struggling to make ends meet,Luo now earns as much as 28,000 yuan($3,868)annually from tea plantation on her 8 mu(0.53 hectares)of land in Pu’er,Yunnan Province.The modernisation of farming and the use of high technology have become a daily reality for farmers and significantly boosted their incomes.展开更多
The discovery of advanced materials is a cornerstone of human technological development and progress.The structures of materials and their corresponding properties are essentially the result of a complex interplay of ...The discovery of advanced materials is a cornerstone of human technological development and progress.The structures of materials and their corresponding properties are essentially the result of a complex interplay of multiple degrees of freedom such as lattice,charge,spin,symmetry,and topology.This poses significant challenges for the inverse design methods of materials.Humans have long explored new materials through numerous experiments and proposed corresponding theoretical systems to predict new material properties and structures.With the improvement of computational power,researchers have gradually developed various electronic-structure calculation methods,such as the density functional theory and high-throughput computational methods.Recently,the rapid development of artificial intelligence(AI)technology in computer science has enabled the effective characterization of the implicit association between material properties and structures,thus forming an efficient paradigm for the inverse design of functional materials.Significant progress has been achieved in the inverse design of materials based on generative and discriminative models,attracting widespread interest from researchers.Considering this rapid technological progress,in this survey,we examine the latest advancements in AI-driven inverse design of materials by introducing the background,key findings,and mainstream technological development routes.In addition,we summarize the remaining challenges for future directions.This survey provides the latest overview of AI-driven inverse design of materials,which can serve as a useful resource for researchers.展开更多
We investigate magnonic topology in the breathing Su–Schrieffer–Heeger(SSH) model, incorporating non-Hermitian effects. Our results demonstrate the coexistence of first-and second-order magnonic topologies, with non...We investigate magnonic topology in the breathing Su–Schrieffer–Heeger(SSH) model, incorporating non-Hermitian effects. Our results demonstrate the coexistence of first-and second-order magnonic topologies, with non-Hermitian effects exhibiting size-dependent behavior. In two-dimensional systems, non-Hermitian terms induce a flat band and gap closure along high-symmetry paths, whereas in one-dimensional systems, a finite band gap persists for small system sizes. Additionally, the corner states remain robust, and a pronounced non-Hermitian skin effect emerges. Our findings provide new insights into magnon-based devices, emphasizing the impact of non-Hermitian effects on their design and functionality.展开更多
With the advent of in-wheel motors and corner modules,the structure of vehicle chassis subsystems has shifted from traditionally centralized to distributed.This review focuses on the distributed chassis system(DCS)equ...With the advent of in-wheel motors and corner modules,the structure of vehicle chassis subsystems has shifted from traditionally centralized to distributed.This review focuses on the distributed chassis system(DCS)equipped with corner modules.It first provides a comprehensive summary and description of the revolution of the structure and control methods of vehicle chassis systems(including driving,braking,suspension,and steering systems).Given that DCS integrates various chassis subsystems,this review moves beyond individual subsystem analysis and delves into the coordination of these subsystems at the vehicle level.It provides a detailed summary of the methods and architectures used for integrated coordination and control,ensuring that multiple subsystems can function seamlessly as an integrated whole.Finally,this review summarizes the latest distributed control architecture for DCS.It also examines current control theories in the fields of control and information technology for distributed systems,such as multi-agent systems and cyber-physical systems.Based on these two control approaches,a multi-domain cooperative control framework for DCS is proposed.展开更多
The intelligent vehicle corner module system,which integrates four-wheel independent drive,independent steering,independent braking and active suspension,can accurately and efficiently perform vehicle driving tasks an...The intelligent vehicle corner module system,which integrates four-wheel independent drive,independent steering,independent braking and active suspension,can accurately and efficiently perform vehicle driving tasks and is the best carrier of intelligent vehicles.Nevertheless,too many angle/torque control inputs make control difficult and non-real-time.In this paper,a hierarchical real-time motion control framework for corner module configuration intelligent electric vehicles is proposed.In the trajectory planning module,an improved driving risk field is designed to describe the surrounding environment’s driving risk.Combined with the kinematic vehicle-road model,model predictive control(MPC)method,spline curve method,the local reference trajectory of safety,comfort and smoothness is planned in real time.The optimal steering angle is determined using MPC method in path tracking module.In the motion control module,a feedforward-feedback controller assigns the optimal steering angle to the front/rear axles,and an angle allocation controller distributes the target angles of the front/rear axles to four steered wheels.Finally,the PreScan-Simulink-CarSim joint simulation environment is established for conducting the human-in-the-loop emergency obstacle avoidance experiment.It took only 0.005 s for the hierarchical motion control system to determine its average solution time.This proves the effectiveness of the hierarchical motion control system.展开更多
Three-dimensional(3D)cell spheroids,generated utilizing the self-organizing properties of mammalian cells,exhibit significant advantages and hold important value in simulating tissue complexity.However,they still enco...Three-dimensional(3D)cell spheroids,generated utilizing the self-organizing properties of mammalian cells,exhibit significant advantages and hold important value in simulating tissue complexity.However,they still encounter numerous limitations,including the absence of spatial anisotropy in cell spheroids,which can compromise their reliability in numerous preclinical drug tests.This study utilizes two-photon polymerization(TPP)3D printing technology,drawing inspiration from common liquid transport structures in nature,to design a microstructure featuring periodic parallel microcavities and wedge angles.This design enables unilateral immobilization and capillary rise of soft condensed matter.This structure facilitates the directed migration of 3D cell spheroids through the physical properties of the structure itself in static culture.Consequently,the original 3D cultured cell spheroids can acquire unique anisotropy within the spatial structure in a static culture environment,presenting a novel perspective for constructing biological constructs and cultivating connections between various cell spheroids,such as organoids.展开更多
基金the National Natural Science Foundation of China (50122155)
文摘Based on the dynamics of ABS-equipped vehicles during cornering braking, the electronic brake- force distribution (EBD) control methods of ABS-equipped vehicles during cornering braking are proposed. According to the dynamics and the tire model under tire adhesion limit, the stability acceptance criteria of vehicles during cornering braking are proposed. According to the stability acceptance criteria and the ABS control, the EBD control methods of ABS-equipped vehicles during cornering braking are implemented by adjusting the threshold values of tires slip independently. The vehicle states during cornering braking at two typical initial velocities of the vehicle are analyzed by the EBD control methods, whose results indicate the EBD control methods can improve the braking performances of the vehicle during cornering braking comparing with the ABS control.
基金supported by the Explore Research Project of the General Armament Department (No. NHA13002)the Fundamental Research Funds for the Central Universities (No.NP2016412)the National Natural Science Foundation of China(No.51505261)
文摘Mechanical elastic wheel(ME-wheel)is a new type of non-inflatable safety tyre,and the structure is significantly different from traditional pneumatic tyre.In order to investigate cornering properties of ME-wheel,experimental research on mechanics characteristics of ME-wheel under steady-state cornering conditions are carried out.The test of steady-state cornering properties of ME-wheel at different experimental parameter conditions is conducted by test bench for dynamic mechanical properties of tyre.Cornering property curves are used to analyze the steady-state cornering properties of ME-wheel,namely the variation tendency of lateral force or aligning torque with the increase of side-slip angle.Moreover,evaluation indexes for cornering properties of ME-wheel are extracted and the effect of different experimental parameters(including vertical load,friction coefficient,and speed)on cornering properties of ME-wheel is contrastively analyzed.The proposed research can provide certain reference to facilitate structure parameters and cornering properties optimizing process of ME-wheel.
基金Project (Nos. 50475009 and 50775096) supported by the National Natural Science Foundation of China
文摘To improve the handling performance of a steer-by-wire (SBW) vehicle, a series of control logics are proposed. Firstly, an algorithm for enhancing the maneuvering in steady-state cornering is presented. On this basis, two categories of control strategies are used to dynamically correct and compensate the transient state steering responses and vehicle behaviors. Simulator tests including subjective evaluations and virtual field tests are both conducted to make comprehensive investigations on the series of control logics. The subjective evaluations demonstrate that the SBW vehicle with a specifically selected value of steering sensitivity tends to be more desirable for driving than a conventional one in which a fixed steering ratio exists. The virtual field tests indicate that the control strategies for dynamical correction and compensation could effectively improve the handling per-formances of an SBW vehicle by reducing the work load of drivers, enhancing the track-holding performance, and improving steering response properties.
基金supported by the National Natural Science Foundation of China(Grant No.51205153)the Natural Science Foundation of Jilin Province(Grant No.20140101072JC)the 2018"13th Five-Year"Scientific Research Planning Project of the Education Department of Jilin Province as well as the 2018 Science and Technology Development Plan of Jilin Province-International Science and Technology Cooperation Project(Grant No.20180414011GH)
文摘Although electric vehicle fully exhibits its comparative merits of energy conservation and environmental friendliness, further improvement of its traction energy efficiency lacks comprehensive investigations in the past. In this paper, the effect of the torque vectoring on traction energy conservation during cornering for a rear-wheel-independent-drive electric vehicle is investigated.Firstly, turning resistance coefficient and energy conservation mechanism of torque vectoring are derived from the single track dynamic model. Next, an optimal torque vectoring control strategy based on genetic algorithm is proposed, with the consideration of the influence of the operation-point change of the in-wheel motors, to find out the best torque vectoring ratio offline. Finally,various simulation tests are conducted to validate the energy conservation effect after Simulink modelling. The results verify that though the optimization of the operating region of the motors is the main part for tractive energy conservation, the contribution of torque vectoring itself can reach up to 1.7% in some typical cases.
文摘Dear colleagues,authors,reviewers,and readers,As we bid farewell to another remarkable year,I am filled with immense gratitude and pride for the strides we have made together in advancing the field of neural regeneration.On behalf of Neural Regeneration Research(NRR),I extend my heartfelt thanks to our dedicated editorial board members,reviewers,authors,readers,and the NRR staff.Your unwavering commitment and support have been the cornerstone of our success,and without your contributions,the journal would not have achieved the milestones we celebrate today.
基金Supported by National Natural Science Foundation of China(Grant Nos.52405112,U24A20199)the Postdoctoral Fellowship Program of CPSF(Grant No.GZB20240973).
文摘Four-Wheel Independent Steering(4WIS)Vehicles can independently control the angle of each wheel,demonstrating superior trajectory tracking performance under normal conditions.However,on intermittent icy and snowy roads,the presence of time-varying adhesion coefficients,time-varying cornering stiffness,and the irregularities due to ice and snow accumulation introduce multiple uncertainties into the steering system,significantly degrading the trajectory tracking performance of 4WIS vehicles.In response,this paper proposes a robust Tube Model Predictive Control(Tube-MPC)trajectory tracking control method for 4WIS.In this method,a Bi-directional Long Short-Term Memory neural network is established for online estimation of tire cornering stiffness under different road adhesion coefficients,providing accurate estimation of time-varying cornering stiffness for each wheel to mitigate the uncertainties of time-varying adhesion coefficients and cornering stiffness.Additionally,considering the road irregularities caused by snow accumulation on intermittent icy and snowy roads,a trajectory tracking controller that integrates Tube-MPC and robust Sliding Mode Control is proposed.The nominal MPC model,developed from the estimated tire cornering stiffness,utilizes the sliding surface and the optimal auxiliary control unit law for the tube is derived from the reaching law in Tube-MPC,aiming to minimize the trajectory tracking error while enhancing the controller’s robustness against road uncertainties.The experiments show that the proposed method outperforms the Tube-MPC algorithm in terms of trajectory accuracy and robustness.This method demonstrates excellent trajectory tracking accuracy under intermittent icy and snowy road conditions,and it lays a theoretical foundation for future studies on vehicle stability and trajectory tracking under such road conditions.
基金supported by the National Natu-ral Science Foundation of China(Grants No.12174220 and No.12074217)the Shandong Provincial Science Foundation for Excellent Young Scholars(Grant No.ZR2023YQ001)+1 种基金the Taishan Young Scholar Program of Shandong Provincethe Qilu Young Scholar Pro-gram of Shandong University.
文摘Higher-order band topology not only enriches our understanding of topological phases but also unveils pioneering lower-dimensional boundary states,which harbors substantial potential for next-generation device applications.The distinct electronic configurations and tunable attributes of two-dimensional materials position them as a quintessential platform for the realization of second-order topological insulators(SOTIs).This article provides an overview of the research progress in SOTIs within the field of two-dimensional electronic materials,focusing on the characterization of higher-order topological properties and the numerous candidate materials proposed in theoretical studies.These endeavors not only enhance our understanding of higher-order topological states but also highlight potential material systems that could be experimentally realized.
基金co-supported by the National Natural Science Foundation of China(No.52406041)the China Postdoctoral Science Foundation(No.2025M774200)the National Science and Technology Major Project of China(No.2019-Ⅱ-0003-0023)。
文摘Currently,the design of advanced compressor blades has reached the full ThreeDimensional(3D)modeling stage.When analyzing the reasons for the failure of popular corner stall prediction criteria for axial compressors to predict the corner flow state in modern compressor3D blades with end-bend and composite bend-sweep characteristics,it is believed that,in addition to the dihedral angle factor in the corner,the variation of the dihedral angle along the flow path is an important factor that has not been considered to date.In light of this,this study first uses the characteristic effects of the diffuser on the deceleration and pressure increase in airflow to design a series of physical models of varying dihedral angle diffusers that are equivalent to compressors.Based on these models,a quantization parameter is established to characterize the development speed of the intersection of boundary layers at the corner under varying dihedral angle and adverse pressure gradient conditions.After combining this with the effects of secondary flow,a Modified diffusion factor DJ(MDJ)is developed to describe the development of corner flow from the leading edge of the blade to its trailing edge under varying dihedral angle conditions.Finally,based on a compressor cascade database,an improved criterion for predicting corner stall in axial compressors using the MDJ diffusion factor is proposed.The validation results,based on extensive experimental data of compressor blades,reveal that this improved criterion can significantly enhance the accuracy of corner stall predictions in the 3D blades of modern compressors compared to currently used prediction criteria,by taking into account the effects of variations in the dihedral angle.
基金Projects(51878103,52208370)supported by the National Natural Science Foundation of ChinaProject(cstc2020jcyjcxtt X0003)supported by the Innovation Group Science Foundation of the Natural Science Foundation of Chongqing,ChinaProject(2022CDJQY-012)supported by the Fundamental Research Funds for the Central Universities,China。
文摘To understand the specific behaviors of coastal coral sand slope foundations,discrete element method(DEM)was employed to examine the effect of breakable particle corners on the performance of coral sand slope foundations under a strip footing,from macro to micro scales.The results demonstrate that the bearing characteristics of coral sand slope foundations can be successfully modeled by utilizing breakable corner particles in simulations.The dual effects of interlocking and breakage of corners well explained the specific shallower load transmission and narrower shear stress zones in breakable corner particle slopes.Additionally,the study revealed the significant influence of breakable corners on soil behaviors on slopes.Furthermore,progressive corner breakage within slip bands was successfully identified as the underling mechanism in determining the unique bearing characteristics and the distinct failure patterns of breakable corner particle slopes.This study provides a new perspective to clarify the behaviors of slope foundations composed of breakable corner particle materials.
基金supported by the Natural Science Basic Research Program of Shaanxi Province(No.2024JC-JCQN-06)the National Natural Science Foundation of China(Nos.12474337,12304370)Fundamental Research Funds for the Central Universities(No.xzy012024135).
文摘Topological insulators represent a new phase of matter,characterized by conductive surfaces,while their bulk remains insulating.When the dimension of the system exceeds that of the topological state by at least two,the insulators are classified as higher-order topological insulators(HOTI).The appearance of higher-order topological states,such as corner states,can be explained by the filling anomaly,which leads to the fractional spectral charges in the unit cell.Previously reported fractional charges have been quite limited in number and size.In this work,based on the two-dimensional(2D)Su-Schrieffer-Heeger model lattice,we demonstrated a new class of HOTIs with adjustable fractional charges that can take any value ranging from 0 to 1,achieved by utilizing the Lorentz transformation.Furthermore,this transformation generates novel bound-state-in-continuum-like corner states,even when the lattice is in a topological trivial phase,offering a new approach to light beam localization.This work paves the way for fabricating HOTIs with diverse corner states that offer promising applicative potential.
文摘Governing technology with technology will be a cornerstone of intelligent communication in the AI era.WITH the rapid development of information technology,the media industry is undergoing unprecedented changes.It has evolved from Internet-based communication and communication on social media platforms to intelligent communication.The revolution of science and technology has always been a core force driving changes in the media.
文摘Investment remains a cornerstone of China’s economic resilience amid global headwinds and structural transitions.In the short term,it drives sectoral growth,creates jobs,and stabilizes economic momentum.Over the long term,a well-structured investment allocation fuels industrial innovation and upgrading,laying a solid foundation for sustainable economic development.
文摘Mutual learning is a cornerstone for building a global community of shared future.Cultural Envoys:Connecting Civilizations introduces the winners of the Orchid Awards,a recent laurel instituted by the China International Communications Group to recognize the work of people worldwide who have made significant contributions to cultural exchanges and mutual learning between China and the rest of the world.
文摘As human society progresses,it faces a range of complex and unprecedented challenges.These include the global energy crisis,environmental degradation,antibiotic resistance,an aging population,and the rapid rise of artificial intelligence(AI).Addressing these issues demands innovative solutions.Historically,scientific discovery has been the cornerstone for overcoming such challenges and driving sustainable development.Yet,as research continues to evolve,achieving breakthroughs that fundamentally shift paradigms-those that take us from"0-1"-is becoming increasingly difficult.One source of untapped innovation lies in nature,a profound teacher from which humans have drawn inspiration for millennia.Through evolution,various species have developed extraordinary strategies to survive and adapt to their environments.This accumulated wisdom offers invaluable insights for advancing science and technology.For instance,the adaptive color change of the chameleon allows it to camouflage,communicate,and regulate its body temperature.Similarly,the electric eel has evolved specialized cells that produce powerful electric currents for defense and hunting.The collective behavior of bees,where individuals follow simple rules to achieve complex group functions,has inspired the development of distributed systems in robotics and AI.Additionally,the nanostructure of cicada wings,which display outstanding optical control and microbial resistance,has informed cutting-edge innovations in materials science,rivaling even the most advanced human technologies.
文摘Farmer Luo Baozhen receives regular weather updates on her smartphone,which help her to better manage her tea farm.Once living in precarious conditions and struggling to make ends meet,Luo now earns as much as 28,000 yuan($3,868)annually from tea plantation on her 8 mu(0.53 hectares)of land in Pu’er,Yunnan Province.The modernisation of farming and the use of high technology have become a daily reality for farmers and significantly boosted their incomes.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.62476278,12434009,and 12204533)supported by the National Key R&D Program of China(Grant No.2024YFA1408601)the Innovation Program for Quantum Science and Technology(Grant No.2021ZD0302402)。
文摘The discovery of advanced materials is a cornerstone of human technological development and progress.The structures of materials and their corresponding properties are essentially the result of a complex interplay of multiple degrees of freedom such as lattice,charge,spin,symmetry,and topology.This poses significant challenges for the inverse design methods of materials.Humans have long explored new materials through numerous experiments and proposed corresponding theoretical systems to predict new material properties and structures.With the improvement of computational power,researchers have gradually developed various electronic-structure calculation methods,such as the density functional theory and high-throughput computational methods.Recently,the rapid development of artificial intelligence(AI)technology in computer science has enabled the effective characterization of the implicit association between material properties and structures,thus forming an efficient paradigm for the inverse design of functional materials.Significant progress has been achieved in the inverse design of materials based on generative and discriminative models,attracting widespread interest from researchers.Considering this rapid technological progress,in this survey,we examine the latest advancements in AI-driven inverse design of materials by introducing the background,key findings,and mainstream technological development routes.In addition,we summarize the remaining challenges for future directions.This survey provides the latest overview of AI-driven inverse design of materials,which can serve as a useful resource for researchers.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 12347156, 12174157, 12074150, and 12174158)the National Key Research and Development Program of China (Grant No. 2022YFA1405200)+1 种基金the Natural Science Foundation of Jiangsu Province (Grant No. BK20230516)the Scientific Research Project of Jiangsu University (Grant No. 550171001)。
文摘We investigate magnonic topology in the breathing Su–Schrieffer–Heeger(SSH) model, incorporating non-Hermitian effects. Our results demonstrate the coexistence of first-and second-order magnonic topologies, with non-Hermitian effects exhibiting size-dependent behavior. In two-dimensional systems, non-Hermitian terms induce a flat band and gap closure along high-symmetry paths, whereas in one-dimensional systems, a finite band gap persists for small system sizes. Additionally, the corner states remain robust, and a pronounced non-Hermitian skin effect emerges. Our findings provide new insights into magnon-based devices, emphasizing the impact of non-Hermitian effects on their design and functionality.
基金Supported by National Natural Science Foundation of China(Grant Nos.52072072,52025121,52394263).
文摘With the advent of in-wheel motors and corner modules,the structure of vehicle chassis subsystems has shifted from traditionally centralized to distributed.This review focuses on the distributed chassis system(DCS)equipped with corner modules.It first provides a comprehensive summary and description of the revolution of the structure and control methods of vehicle chassis systems(including driving,braking,suspension,and steering systems).Given that DCS integrates various chassis subsystems,this review moves beyond individual subsystem analysis and delves into the coordination of these subsystems at the vehicle level.It provides a detailed summary of the methods and architectures used for integrated coordination and control,ensuring that multiple subsystems can function seamlessly as an integrated whole.Finally,this review summarizes the latest distributed control architecture for DCS.It also examines current control theories in the fields of control and information technology for distributed systems,such as multi-agent systems and cyber-physical systems.Based on these two control approaches,a multi-domain cooperative control framework for DCS is proposed.
基金Supported by National Natural Science Foundation of China(Grant No.52332013)。
文摘The intelligent vehicle corner module system,which integrates four-wheel independent drive,independent steering,independent braking and active suspension,can accurately and efficiently perform vehicle driving tasks and is the best carrier of intelligent vehicles.Nevertheless,too many angle/torque control inputs make control difficult and non-real-time.In this paper,a hierarchical real-time motion control framework for corner module configuration intelligent electric vehicles is proposed.In the trajectory planning module,an improved driving risk field is designed to describe the surrounding environment’s driving risk.Combined with the kinematic vehicle-road model,model predictive control(MPC)method,spline curve method,the local reference trajectory of safety,comfort and smoothness is planned in real time.The optimal steering angle is determined using MPC method in path tracking module.In the motion control module,a feedforward-feedback controller assigns the optimal steering angle to the front/rear axles,and an angle allocation controller distributes the target angles of the front/rear axles to four steered wheels.Finally,the PreScan-Simulink-CarSim joint simulation environment is established for conducting the human-in-the-loop emergency obstacle avoidance experiment.It took only 0.005 s for the hierarchical motion control system to determine its average solution time.This proves the effectiveness of the hierarchical motion control system.
基金supported by the National Natural Science Foundation of China(Grant Nos.T2350007 and 12174041)the Natural Science Foundation of Chongqing(Grant No.CSTB2024NSCQ-MSX0596)+1 种基金the Science and Technology Research Program of Chongqing Municipal Education Commission(Grant No.KJZD-K202401306)the Scientific Research Fund of Chongqing University of Arts and Sciences(Grant Nos.R2023HH03 and P2022HH05)。
文摘Three-dimensional(3D)cell spheroids,generated utilizing the self-organizing properties of mammalian cells,exhibit significant advantages and hold important value in simulating tissue complexity.However,they still encounter numerous limitations,including the absence of spatial anisotropy in cell spheroids,which can compromise their reliability in numerous preclinical drug tests.This study utilizes two-photon polymerization(TPP)3D printing technology,drawing inspiration from common liquid transport structures in nature,to design a microstructure featuring periodic parallel microcavities and wedge angles.This design enables unilateral immobilization and capillary rise of soft condensed matter.This structure facilitates the directed migration of 3D cell spheroids through the physical properties of the structure itself in static culture.Consequently,the original 3D cultured cell spheroids can acquire unique anisotropy within the spatial structure in a static culture environment,presenting a novel perspective for constructing biological constructs and cultivating connections between various cell spheroids,such as organoids.