Aiming to solve the steering instability and hysteresis of agricultural robots in the process of movement,a fusion PID control method of particle swarm optimization(PSO)and genetic algorithm(GA)was proposed.The fusion...Aiming to solve the steering instability and hysteresis of agricultural robots in the process of movement,a fusion PID control method of particle swarm optimization(PSO)and genetic algorithm(GA)was proposed.The fusion algorithm took advantage of the fast optimization ability of PSO to optimize the population screening link of GA.The Simulink simulation results showed that the convergence of the fitness function of the fusion algorithm was accelerated,the system response adjustment time was reduced,and the overshoot was almost zero.Then the algorithm was applied to the steering test of agricultural robot in various scenes.After modeling the steering system of agricultural robot,the steering test results in the unloaded suspended state showed that the PID control based on fusion algorithm reduced the rise time,response adjustment time and overshoot of the system,and improved the response speed and stability of the system,compared with the artificial trial and error PID control and the PID control based on GA.The actual road steering test results showed that the PID control response rise time based on the fusion algorithm was the shortest,about 4.43 s.When the target pulse number was set to 100,the actual mean value in the steady-state regulation stage was about 102.9,which was the closest to the target value among the three control methods,and the overshoot was reduced at the same time.The steering test results under various scene states showed that the PID control based on the proposed fusion algorithm had good anti-interference ability,it can adapt to the changes of environment and load and improve the performance of the control system.It was effective in the steering control of agricultural robot.This method can provide a reference for the precise steering control of other robots.展开更多
Chinese President Xi Jinping has guided China through a year of resilient growth via forward-looking reforms and innovation-driven transformation that is shaping the nation’s economic trajectory for 2026 and beyond.
Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significan...Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significant gap in detailed and consistent data on 3D building space structures with global coverage due to the challenges inherent in the data collection and model calibration processes.In this study,we constructed a global urban structure(GUS-3D)dataset,including building volume,height,and footprint information,at a 500 m spatial resolution using extensive satellite observation products and numerous reference building samples.Our analysis indicated that the total volume of buildings worldwide in2015 exceeded 1×10^(12)m^(3).Over the 1985 to 2015 period,we observed a slight increase in the magnitude of 3D building volume growth(i.e.,it increased from 166.02 km3 during the 1985–2000 period to 175.08km3 during the 2000–2015 period),while the expansion magnitudes of the two-dimensional(2D)building footprint(22.51×10^(3) vs 13.29×10^(3)km^(2))and urban extent(157×10^(3) vs 133.8×10^(3)km^(2))notably decreased.This trend highlights the significant increase in intensive vertical utilization of urban land.Furthermore,we identified significant heterogeneity in building space provision and inequality across cities worldwide.This inequality is particularly pronounced in many populous Asian cities,which has been overlooked in previous studies on economic inequality.The GUS-3D dataset shows great potential to deepen our understanding of the urban environment and creates new horizons for numerous 3D urban studies.展开更多
To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D lea...To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D leader-following cooperative interception guidance law.First,in the LOS direction of the leader,an impact time-controlled guidance law is derived based on the fixed-time stability theory,which enables the leader to complete the interception task at a prespecified impact time.Next,in the LOS direction of the followers,by introducing a time consensus tracking error function,a fixed-time consensus tracking guidance law is investigated to guarantee the consensus tracking convergence of the time-to-go.Then,in the direction normal to the LOS,by combining the designed global integral sliding mode surface and the second-order Sliding Mode Control(SMC)theory,an innovative 3D LOS-angle-constrained interception guidance law is developed,which eliminates the reaching phase in the traditional sliding mode guidance laws and effectively saves energy consumption.Moreover,it effectively suppresses the chattering phenomenon while avoiding the singularity issue,and compensates for unknown interference caused by target maneuvering online,making it convenient for practical engineering applications.Finally,theoretical proof analysis and multiple sets of numerical simulation results verify the effectiveness,superiority,and robustness of the investigated guidance law.展开更多
Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma ...Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma pathobiology.Conventional cell culture-based research(2D cell culture)is still playing a pivotal role,while several shortcomings have been recently under discussion.In vivo,mouse models are usually adopted for pre-clinical analyses with expectations to overcome the issues of 2D cell culture.However,they do not fully recapitulate human dedifferentiated liposarcoma(DDLPS)characteristics.Therefore,three-dimensional(3D)culture systems have been the recent research focus in the cell biology field with the expectation to overcome at the same time the disadvantages of 2D cell culture and in vivo animal models and fill in the gap between them.Given the liposarcoma rarity,we believe that 3D cell culture techniques,including 3D cell cultures/co-cultures,and Patient-Derived tumor Organoids(PDOs),represent a promising approach to facilitate liposarcoma investigation and elucidate its molecular mechanisms and effective therapy development.In this review,we first provide a general overview of 3D cell cultures compared to 2D cell cultures.We then focus on one of the recent 3D cell culture applications,Patient-Derived Organoids(PDOs),summarizing and discussing several PDO methodologies.Finally,we discuss the current and future applications of PDOs to sarcoma,particularly in the field of liposarcoma.展开更多
Research has shown that when vehicles follow the Ackerman steering principle(ASP),the tire wear can be reduced and the path tracking performance can be improved.However,in the case of four-wheel independent steering(4...Research has shown that when vehicles follow the Ackerman steering principle(ASP),the tire wear can be reduced and the path tracking performance can be improved.However,in the case of four-wheel independent steering(4WIS)vehicles,the steering systems of the four wheels are relatively independent,and there are differences and uncertainties in individual steering dynamics,which lead to challenges for all four wheels in simultaneously satisfying the ASP and may deteriorate the vehicle path tracking performance.In response to this problem,this paper introduces a four-wheel consistent coordinated steering control for 4WIS vehicles.The algorithm innovatively reconfigures the Ackerman steering relationships as coupling constraints among the wheels,and utilizes the constraint-following method to design controller.The controller achieves uniform boundedness(UB)and uniform ultimate boundedness(UUB)of ASP constraint error.The Carsim/Simulink joint simulation results demonstrate that the algorithm guarantees the approximate satisfaction of ASP in both the transient and steady-state of the vehicle path tracking.Also,it significantly improves the path tracking performance.展开更多
During aircraft ground steering,the nose landing gear(NLG)tires of large transport aircraft often experience excessive lateral loads,leading to sideslip.This compromises steering safety and accelerates tire wear.To ad...During aircraft ground steering,the nose landing gear(NLG)tires of large transport aircraft often experience excessive lateral loads,leading to sideslip.This compromises steering safety and accelerates tire wear.To address this issue,the rear landing gear is typically designed to steer in coordination with the nose wheels,reducing sideslip and improving maneuverability.This study examines how structural parameters and weight distribution affect the performance of coordinated steering in landing gear design for large transport aircraft.Using the C-5 transport aircraft as a case study,we develop a multi-wheel ground steering dynamics model,incorporating the main landing gear(MLG)deflection.A ground handling dynamics model is also established to evaluate the benefits of coordinated steering for rear MLG during steering.Additionally,the study analyzes the impact of structural parameters such as stiffness and damping on the steering performance of the C-5.It further investigates the effects of weight distribution,including the center-of-gravity(CG)height,the longitudinal CG position,and the mass asymmetry.Results show that when the C-5 employs coordinated steering for rear MLG,the lateral friction coefficients of the NLG tires decrease by 22%,24%,26%,and 27%.The steering radius is reduced by 29.7%,and the NLG steering moment decreases by 19%,significantly enhancing maneuverability.Therefore,in the design of landing gear for large transport aircraft,coordinated MLG steering,along with optimal structural and CG position parameters,should be primary design objectives.These results provide theoretical guidance for the design of multi-wheel landing gear systems in large transport aircraft.展开更多
The development of minimally invasive surgery has transformed the management of gastrointestinal cancer.Notably,three-dimensional visualization systems have increased surgical precision.This editorial discusses a rece...The development of minimally invasive surgery has transformed the management of gastrointestinal cancer.Notably,three-dimensional visualization systems have increased surgical precision.This editorial discusses a recent study by Shen and Zhang,which compared the clinical applications of naked-eye threedimensional laparoscopic systems vs traditional optical systems in radical surgery for gastric and colorectal cancer.Both systems appeared to yield comparable surgical and oncological outcomes in terms of safety parameters,operating times,and quality of lymph node dissection.However,the spectacle-free system’s technical and logistical limitations hindered its effects on the surgical team’s overall competency.This editorial examines the authors’findings within the broader context of the evolution of oncologic laparoscopy,discusses the relevance of the results in light of the current literature,and proposes future research directions focused on multicenter validation,comprehensive ergonomic analysis,and technological advancements aimed at enhancing intraoperative collaboration.As technology continues to evolve,clinical implementation of new methods must be supported by robust scientific evidence and standardized criteria,to ensure tangible improvements in efficiency,safety,and oncologic outcomes.展开更多
This study aims to enhance the maneuvering advantages of the waterjet unit through parametric design,performance evaluation,and optimization of the one-piece waterjet propulsion steering and reversing gear(SRG).The SR...This study aims to enhance the maneuvering advantages of the waterjet unit through parametric design,performance evaluation,and optimization of the one-piece waterjet propulsion steering and reversing gear(SRG).The SRG’s performance evaluation stems mainly from the effect of the free surface,the varying sailing speeds of the ship,and its performance while functioning at the stern of the waterjet-propelled vessel.Parameters such as the length,width,and height of the steering gear,as well as the inclination,width,and curvature of the reversing gear,significantly influence the SRG.Although the free surface has a great impact on the force of the SRG,its performance trend remains unaffected.When the SRG operates at the stern of the ship,the optimized scheme’s lateral force improves by an average of 8.08%for sailing with a rudder angle condition and an average of 45.69%for reversing sailing with a rudder angle condition.The longitudinal force of the optimized scheme improves by more than 23%when sailing without a rudder angle condition and by an average of 31.75%when sailing with a reversed rudder angle condition.Additionally,the speed of the rotor has a minimal effect on the lateral force and a significant effect on the longitudinal force.展开更多
From October 30 to November 1,2025,Chinese President Xi Jinping traveled to the Republic of Korea(ROK)to attend the 32nd Asia-Pacific Economic Cooperation(APEC)Economic Leaders’Meeting and also pay a state visit to t...From October 30 to November 1,2025,Chinese President Xi Jinping traveled to the Republic of Korea(ROK)to attend the 32nd Asia-Pacific Economic Cooperation(APEC)Economic Leaders’Meeting and also pay a state visit to the country.This was Xi Jinping’s first overseas trip following the conclusion of the fourth plenary session of the 20th Communist Party of China Central Committee,underscoring its importance on China’s diplomatic agenda.展开更多
With the urgently increasing demand for high-speed and large-capacity communication trans-mission,there remains a critical need for tunable terahertz(THz)devices with multi-channel in 5G/6G communication systems.A mag...With the urgently increasing demand for high-speed and large-capacity communication trans-mission,there remains a critical need for tunable terahertz(THz)devices with multi-channel in 5G/6G communication systems.A magnetic phase-coding meta-atom(MPM)is formed by the heterogeneous integration of La:YIG magneto-optical(MO)materials and Si microstructures.The MPM couples the magnetic induction phase of spin states with the propagation phase and can simultaneously satisfy the required output phase for dual frequencies under various external magnetic fields to realize the dynamic beam steering among multiple channels at 0.25 and 0.5 THz.The energy ratio of the target direction can reach 96.5%,and the nonreciprocal one-way transmission with a max isolation of 29.8 dB is realized due to the nonreciprocal phase shift of the MO layer.This nonreciprocal mechanism of magnetic induction reshaping of wavefront significantly holds promise for advancing integrated multi-functional THz devices with the characteristics of low-crosstalk,multi-channel,and multi-frequency,and has great potential to promote the development of THz large-capacity and high-speed communication.展开更多
We theoretically demonstrate that multipartite entanglement and one-way Einstein-Podolsky-Rosen(EPR)steering in a magnon frequency comb(MFC)can be generated in a hybrid magnon-skyrmion system.When the system is driven...We theoretically demonstrate that multipartite entanglement and one-way Einstein-Podolsky-Rosen(EPR)steering in a magnon frequency comb(MFC)can be generated in a hybrid magnon-skyrmion system.When the system is driven by two microwave fields at the magnonic whispering gallery mode(m WGM)and the skyrmion,the skyrmion can be simultaneously entangled with three magnon modes of the MFC and the entanglement of the first-order magnon pair in the MFC also appears.The results show that the perfect one-way steering between the skyrmion and the three magnons can be obtained.Interestingly,the steering direction can be manipulated by controlling the amplitudes of two drive fields,which provides flexibility in controlling the asymmetry of the EPR steering and may well have practical applications.Moreover,the genuine tripartite entanglement among the skyrmion and the first-order magnon pair can be achieved with appropriate parameters in the steady state.Our work exhibits that the MFC has great potential in preparing multi-mode entanglement resources,with promising applications in quantum communication.展开更多
We introduce a novel scheme for achieving quantum entanglement and Einstein–Podolsky–Rosen(EPR) steering between an atomic ensemble and a mechanical oscillator within a hybrid atom–optomechanical system. The system...We introduce a novel scheme for achieving quantum entanglement and Einstein–Podolsky–Rosen(EPR) steering between an atomic ensemble and a mechanical oscillator within a hybrid atom–optomechanical system. The system comprises an optical cavity, a two-level atomic ensemble and a mechanical resonator that possesses Duffing nonlinearity. The interaction between these components is mediated by the cavity mode, which is driven by an external laser. Our findings indicate that optimizing the coupling strengths between photons and phonons, as well as between atoms and the cavity,leads to maximal entanglement and EPR steering. The amplitude of the driving laser plays a pivotal role in enhancing the coupling between photons and phonons, and the system maintains robust entanglement and EPR steering even under high dissipation, thereby mitigating the constraints on initial conditions and parameter precision. Remarkably, the Duffing nonlinearity enhances the system's resistance to thermal noise, ensuring its stability and entanglement protection. Our analysis of EPR steering conditions reveals that the party with lower dissipation exhibits superior stability and a propensity to steer the party with higher dissipation. These discoveries offer novel perspectives for advancing quantum information processing and communication technologies.展开更多
President Xi Jinping’s APEC trip underscores China’s resolve to advance openness,cooperation,and shared prosperity across the Asia-Pacific region.FROM October 30 to November 1,2025,Chinese President Xi Jinping trave...President Xi Jinping’s APEC trip underscores China’s resolve to advance openness,cooperation,and shared prosperity across the Asia-Pacific region.FROM October 30 to November 1,2025,Chinese President Xi Jinping traveled to the Republic of Korea(ROK)to attend the 32nd Asia-Pacific Economic Cooperation(APEC)Economic Leaders’Meeting and also pay a state visit to the country.展开更多
The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated cata...The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated catalytic activity and minimal energy consumption continues to pose a significant challenge.In this research,Fluorine-doped copper-carbon(F/Cu-GAC)particle electrodes were effectively synthesized through an impregnationcalcination technique,utilizing granular activated carbon as the carrier and fluorinedoped modified copper oxides as the catalytic agents.The particle electrodes were subsequently utilized to promote the degradation of 2,4,6-trichlorophenol(2,4,6-TCP)in a threedimensional electrocatalytic reactor(3DER).The F/Cu-GAC particle electrodes were polarized under the action of electric field,which promoted the heterogeneous Fenton-like reaction in which H2O2 generated by two-electron oxygen reduction reaction(2e-ORR)of O_(2) was catalytically decomposed to·OH.The 3DER equipped with F/Cu-GAC particle electrodes showed 100%removal of 2,4,6-TCP and 79.24%removal of TOC with a specific energy consumption(EC)of approximately 0.019 kWh/g·COD after 2 h of operation.The F/Cu-GAC particle electrodes exhibited an overpotential of 0.38 V and an electrochemically active surface area(ECSA)of 715 cm^(2),as determined through linear sweep voltammetry(LSV)and cyclic voltammetry(CV)assessments.These findings suggest a high level of electrocatalytic performance.Furthermore,the catalytic mechanism of the 3DER equipped with F/Cu-GAC particle electrodes was elucidated through the application of X-ray photoelectron spectroscopy(XPS),electron spin resonance(ESR),and active species capture experiments.This investigation offers a novel approach for the effective degradation of 2,4,6-TCP.展开更多
In order to enhance the safety of autonomous driving vehicles,this work focuses on the issue of automatic-to-manual mode transition in the column electric power steering(C-EPS)system.First,we utilized an extended stat...In order to enhance the safety of autonomous driving vehicles,this work focuses on the issue of automatic-to-manual mode transition in the column electric power steering(C-EPS)system.First,we utilized an extended state observer to estimate the driver's steering torque and designed a steering mode transition unit.Second,we validated the mode switching function through an experimental platform.The results indicated that when using the extended state observer for torque estimation,the steering wheel angle and lower input angle errors were approximately±0.5%.The input and observed torque curves were closely aligned,demonstrating excellent tracking capability of the system.In addition,by adopting a steering mode conversion unit,the switch from autonomous control to manual control has been obtained,achieving a smooth and minimal change in steering wheel angle without significant bumps.The experimental results demonstrate that the designed mode switching strategy has the advantages of speed and smoothness,and has strong practical value.展开更多
In the parallel steering coordination control strategy for path tracking,it is difficult to match the current driver steering model using the fixed parameters with the actual driver,and the designed steering coordinat...In the parallel steering coordination control strategy for path tracking,it is difficult to match the current driver steering model using the fixed parameters with the actual driver,and the designed steering coordination control strategy under a single objective and simple conditions is difficult to adapt to the multi-dimensional state variables’input.In this paper,we propose a deep reinforcement learning algorithm-based multi-objective parallel human-machine steering coordination strategy for path tracking considering driver misoperation and external disturbance.Firstly,the driver steering mathematical model is constructed based on the driver preview characteristics and steering delay response,and the driver characteristic parameters are fitted after collecting the actual driver driving data.Secondly,considering that the vehicle is susceptible to the influence of external disturbances during the driving process,the Tube MPC(Tube Model Predictive Control)based path tracking steering controller is designed based on the vehicle system dynamics error model.After verifying that the driver steering model meets the driver steering operation characteristics,DQN(Deep Q-network),DDPG(Deep Deterministic Policy Gradient)and TD3(Twin Delayed Deep Deterministic Policy Gradient)deep reinforcement learning algorithms are utilized to design a multi-objective parallel steering coordination strategy which satisfies the multi-dimensional state variables’input of the vehicle.Finally,the tracking accuracy,lateral safety,human-machine conflict and driver steering load evaluation index are designed in different driver operation states and different road environments,and the performance of the parallel steering coordination control strategies with different deep reinforcement learning algorithms and fuzzy algorithms are compared by simulations and hardware in the loop experiments.The results show that the parallel steering collaborative strategy based on a deep reinforcement learning algorithm can more effectively assist the driver in tracking the target path under lateral wind interference and driver misoperation,and the TD3-based coordination control strategy has better overall performance.展开更多
In this study,CiteSpace software is used to carry out visual analysis on the three-dimensional research literature on urban recreation space from the perspective of compact city theory in the past 20 years,exploring t...In this study,CiteSpace software is used to carry out visual analysis on the three-dimensional research literature on urban recreation space from the perspective of compact city theory in the past 20 years,exploring the scientific development trend and research hotspots in this field.The results show that the number of published documents shows a fluctuating upward trend,and the significant growth rate reflects the role of policy orientation in promoting the concept of compact city.The co-occurrence analysis of keywords reveals the research hotspots of“compact city”,“recreation space”and“urban park”,while the emergence of new keywords such as“vertical city”and“spatial justice”indicates the new trend of recent research.The cluster analysis and timeline map further show the evolution of research themes,with“compact city”being the largest cluster and having rich connections with other themes such as“urban design”and“urban park”.展开更多
Thermal metamaterial represents a groundbreaking approach to control heat conduction,and,as a crucial component,thermal invisibility is of utmost importance for heat management.Despite the flourishing development of t...Thermal metamaterial represents a groundbreaking approach to control heat conduction,and,as a crucial component,thermal invisibility is of utmost importance for heat management.Despite the flourishing development of thermal invisibility schemes,they still face two limitations in practical applications.First,objects are typically completely enclosed in traditional cloaks,making them difficult to use and unsuitable for objects with heat sources.Second,although some theoretical proposals have been put forth to change the thermal conductivity of materials to achieve dynamic invisibility,their designs are complex and rigid,making them unsuitable for large-scale use in real threedimensional(3D)spaces.Here,we propose a concept of a thermal dome to achieve 3D invisibility.Our scheme includes an open functional area,greatly enhancing its usability and applicability.It features a reconfigurable structure,constructed with simple isotropic natural materials,making it suitable for dynamic requirements.The performance of our reconfigurable thermal dome has been confirmed through simulations and experiments,consistent with the theory.The introduction of this concept can greatly advance the development of thermal invisibility technology from theory to engineering and provide inspiration for other physical domains,such as direct current electric fields and magnetic fields.展开更多
BACKGROUND Ganglioneuroma is a rare,well-differentiated,slow-growing benign tumor of the peripheral nerves,with surgical resection being the only curative treatment.Surgical resection of ganglioneuromas encasing major...BACKGROUND Ganglioneuroma is a rare,well-differentiated,slow-growing benign tumor of the peripheral nerves,with surgical resection being the only curative treatment.Surgical resection of ganglioneuromas encasing major blood vessels remains a substantial clinical challenge.Traditionally,these cases often require open abdominal surgery or combined organ resections,and in some instances,the tumors are considered unresectable.Currently,no reports have described the resection of such tumors via laparoscopy.CASE SUMMARY A 35-year-old woman was admitted to our hospital after the incidental discovery of a retroperitoneal space-occupying lesion.Imaging revealed a mass with the celiac axis and superior mesenteric artery passing through it.A neurogenic tumor was suspected,with ganglioneuroma being the most likely diagnosis.Following comprehensive preoperative preparation,the retroperitoneal tumor was resected using a three-dimensional laparoscopy combined with an organ suspension technique.The surgical approach involved incising the tumor along the vascular axis and conducting meticulous,vascular-preserving tumor excision.The operation lasted approximately 458 minutes,with an estimated blood loss of 50 mL.The patient was discharged on the 8th postoperative day.A transient liver injury occurred after surgery but improved rapidly.After 11 months of postoperative follow-up,no complications or tumor recurrence were observed.CONCLUSION This case illustrates the feasibility of minimally invasive laparoscopic resection for retroperitoneal ganglioneuromas encasing major blood vessels.展开更多
文摘Aiming to solve the steering instability and hysteresis of agricultural robots in the process of movement,a fusion PID control method of particle swarm optimization(PSO)and genetic algorithm(GA)was proposed.The fusion algorithm took advantage of the fast optimization ability of PSO to optimize the population screening link of GA.The Simulink simulation results showed that the convergence of the fitness function of the fusion algorithm was accelerated,the system response adjustment time was reduced,and the overshoot was almost zero.Then the algorithm was applied to the steering test of agricultural robot in various scenes.After modeling the steering system of agricultural robot,the steering test results in the unloaded suspended state showed that the PID control based on fusion algorithm reduced the rise time,response adjustment time and overshoot of the system,and improved the response speed and stability of the system,compared with the artificial trial and error PID control and the PID control based on GA.The actual road steering test results showed that the PID control response rise time based on the fusion algorithm was the shortest,about 4.43 s.When the target pulse number was set to 100,the actual mean value in the steady-state regulation stage was about 102.9,which was the closest to the target value among the three control methods,and the overshoot was reduced at the same time.The steering test results under various scene states showed that the PID control based on the proposed fusion algorithm had good anti-interference ability,it can adapt to the changes of environment and load and improve the performance of the control system.It was effective in the steering control of agricultural robot.This method can provide a reference for the precise steering control of other robots.
文摘Chinese President Xi Jinping has guided China through a year of resilient growth via forward-looking reforms and innovation-driven transformation that is shaping the nation’s economic trajectory for 2026 and beyond.
基金supported by the National Science Fund for Distinguished Young Scholars(42225107)the National Natural Science Foundation of China(42001326,42371414,42171409,and 42271419)+1 种基金the Natural Science Foundation of Guangdong Province of China(2022A1515012207)the Basic and Applied Basic Research Project of Guangzhou Science and Technology Planning(202201011539)。
文摘Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significant gap in detailed and consistent data on 3D building space structures with global coverage due to the challenges inherent in the data collection and model calibration processes.In this study,we constructed a global urban structure(GUS-3D)dataset,including building volume,height,and footprint information,at a 500 m spatial resolution using extensive satellite observation products and numerous reference building samples.Our analysis indicated that the total volume of buildings worldwide in2015 exceeded 1×10^(12)m^(3).Over the 1985 to 2015 period,we observed a slight increase in the magnitude of 3D building volume growth(i.e.,it increased from 166.02 km3 during the 1985–2000 period to 175.08km3 during the 2000–2015 period),while the expansion magnitudes of the two-dimensional(2D)building footprint(22.51×10^(3) vs 13.29×10^(3)km^(2))and urban extent(157×10^(3) vs 133.8×10^(3)km^(2))notably decreased.This trend highlights the significant increase in intensive vertical utilization of urban land.Furthermore,we identified significant heterogeneity in building space provision and inequality across cities worldwide.This inequality is particularly pronounced in many populous Asian cities,which has been overlooked in previous studies on economic inequality.The GUS-3D dataset shows great potential to deepen our understanding of the urban environment and creates new horizons for numerous 3D urban studies.
文摘To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D leader-following cooperative interception guidance law.First,in the LOS direction of the leader,an impact time-controlled guidance law is derived based on the fixed-time stability theory,which enables the leader to complete the interception task at a prespecified impact time.Next,in the LOS direction of the followers,by introducing a time consensus tracking error function,a fixed-time consensus tracking guidance law is investigated to guarantee the consensus tracking convergence of the time-to-go.Then,in the direction normal to the LOS,by combining the designed global integral sliding mode surface and the second-order Sliding Mode Control(SMC)theory,an innovative 3D LOS-angle-constrained interception guidance law is developed,which eliminates the reaching phase in the traditional sliding mode guidance laws and effectively saves energy consumption.Moreover,it effectively suppresses the chattering phenomenon while avoiding the singularity issue,and compensates for unknown interference caused by target maneuvering online,making it convenient for practical engineering applications.Finally,theoretical proof analysis and multiple sets of numerical simulation results verify the effectiveness,superiority,and robustness of the investigated guidance law.
文摘Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma pathobiology.Conventional cell culture-based research(2D cell culture)is still playing a pivotal role,while several shortcomings have been recently under discussion.In vivo,mouse models are usually adopted for pre-clinical analyses with expectations to overcome the issues of 2D cell culture.However,they do not fully recapitulate human dedifferentiated liposarcoma(DDLPS)characteristics.Therefore,three-dimensional(3D)culture systems have been the recent research focus in the cell biology field with the expectation to overcome at the same time the disadvantages of 2D cell culture and in vivo animal models and fill in the gap between them.Given the liposarcoma rarity,we believe that 3D cell culture techniques,including 3D cell cultures/co-cultures,and Patient-Derived tumor Organoids(PDOs),represent a promising approach to facilitate liposarcoma investigation and elucidate its molecular mechanisms and effective therapy development.In this review,we first provide a general overview of 3D cell cultures compared to 2D cell cultures.We then focus on one of the recent 3D cell culture applications,Patient-Derived Organoids(PDOs),summarizing and discussing several PDO methodologies.Finally,we discuss the current and future applications of PDOs to sarcoma,particularly in the field of liposarcoma.
基金Supported by National Natural Science Foundation of China(Grant Nos.52222216,52202493,52202466,U24B20124)Hunan Provincial Natural Science Foundation of China(Grant No.2022JJ40059).
文摘Research has shown that when vehicles follow the Ackerman steering principle(ASP),the tire wear can be reduced and the path tracking performance can be improved.However,in the case of four-wheel independent steering(4WIS)vehicles,the steering systems of the four wheels are relatively independent,and there are differences and uncertainties in individual steering dynamics,which lead to challenges for all four wheels in simultaneously satisfying the ASP and may deteriorate the vehicle path tracking performance.In response to this problem,this paper introduces a four-wheel consistent coordinated steering control for 4WIS vehicles.The algorithm innovatively reconfigures the Ackerman steering relationships as coupling constraints among the wheels,and utilizes the constraint-following method to design controller.The controller achieves uniform boundedness(UB)and uniform ultimate boundedness(UUB)of ASP constraint error.The Carsim/Simulink joint simulation results demonstrate that the algorithm guarantees the approximate satisfaction of ASP in both the transient and steady-state of the vehicle path tracking.Also,it significantly improves the path tracking performance.
基金supported in part by the Fundamental Research Funds for the Central Universi-ties(No.NP2022416)the Aeronautical Science Founda-tion of China(No.2022Z029052001).
文摘During aircraft ground steering,the nose landing gear(NLG)tires of large transport aircraft often experience excessive lateral loads,leading to sideslip.This compromises steering safety and accelerates tire wear.To address this issue,the rear landing gear is typically designed to steer in coordination with the nose wheels,reducing sideslip and improving maneuverability.This study examines how structural parameters and weight distribution affect the performance of coordinated steering in landing gear design for large transport aircraft.Using the C-5 transport aircraft as a case study,we develop a multi-wheel ground steering dynamics model,incorporating the main landing gear(MLG)deflection.A ground handling dynamics model is also established to evaluate the benefits of coordinated steering for rear MLG during steering.Additionally,the study analyzes the impact of structural parameters such as stiffness and damping on the steering performance of the C-5.It further investigates the effects of weight distribution,including the center-of-gravity(CG)height,the longitudinal CG position,and the mass asymmetry.Results show that when the C-5 employs coordinated steering for rear MLG,the lateral friction coefficients of the NLG tires decrease by 22%,24%,26%,and 27%.The steering radius is reduced by 29.7%,and the NLG steering moment decreases by 19%,significantly enhancing maneuverability.Therefore,in the design of landing gear for large transport aircraft,coordinated MLG steering,along with optimal structural and CG position parameters,should be primary design objectives.These results provide theoretical guidance for the design of multi-wheel landing gear systems in large transport aircraft.
文摘The development of minimally invasive surgery has transformed the management of gastrointestinal cancer.Notably,three-dimensional visualization systems have increased surgical precision.This editorial discusses a recent study by Shen and Zhang,which compared the clinical applications of naked-eye threedimensional laparoscopic systems vs traditional optical systems in radical surgery for gastric and colorectal cancer.Both systems appeared to yield comparable surgical and oncological outcomes in terms of safety parameters,operating times,and quality of lymph node dissection.However,the spectacle-free system’s technical and logistical limitations hindered its effects on the surgical team’s overall competency.This editorial examines the authors’findings within the broader context of the evolution of oncologic laparoscopy,discusses the relevance of the results in light of the current literature,and proposes future research directions focused on multicenter validation,comprehensive ergonomic analysis,and technological advancements aimed at enhancing intraoperative collaboration.As technology continues to evolve,clinical implementation of new methods must be supported by robust scientific evidence and standardized criteria,to ensure tangible improvements in efficiency,safety,and oncologic outcomes.
基金supported by the Sanya Science and Education Innovation Park of Wuhan University of Technology(Grant No.2022KF0017)Hainan Provincial Natural Science Foundation of China(Grant No.522QN342)+1 种基金the National Natural Science Foundation of China(Grant No.52201376)Natural Science Foundation of Hubei Province,China(Grant No.2023AFB683).
文摘This study aims to enhance the maneuvering advantages of the waterjet unit through parametric design,performance evaluation,and optimization of the one-piece waterjet propulsion steering and reversing gear(SRG).The SRG’s performance evaluation stems mainly from the effect of the free surface,the varying sailing speeds of the ship,and its performance while functioning at the stern of the waterjet-propelled vessel.Parameters such as the length,width,and height of the steering gear,as well as the inclination,width,and curvature of the reversing gear,significantly influence the SRG.Although the free surface has a great impact on the force of the SRG,its performance trend remains unaffected.When the SRG operates at the stern of the ship,the optimized scheme’s lateral force improves by an average of 8.08%for sailing with a rudder angle condition and an average of 45.69%for reversing sailing with a rudder angle condition.The longitudinal force of the optimized scheme improves by more than 23%when sailing without a rudder angle condition and by an average of 31.75%when sailing with a reversed rudder angle condition.Additionally,the speed of the rotor has a minimal effect on the lateral force and a significant effect on the longitudinal force.
文摘From October 30 to November 1,2025,Chinese President Xi Jinping traveled to the Republic of Korea(ROK)to attend the 32nd Asia-Pacific Economic Cooperation(APEC)Economic Leaders’Meeting and also pay a state visit to the country.This was Xi Jinping’s first overseas trip following the conclusion of the fourth plenary session of the 20th Communist Party of China Central Committee,underscoring its importance on China’s diplomatic agenda.
基金supported by the National Natural Science Foun-dation of China(Grant Nos.62371258,62335012,62205160,and 62435010)the Tianjin Youth Science and Technology Talent Project(Grant No.QN20230227)+1 种基金the Natural Science Foundation of Tianjin(Grant No.24JCYBJC01860)the Fundamental Research Funds for the Central Universities,Nan-kai University(Grant No.075-63253215).
文摘With the urgently increasing demand for high-speed and large-capacity communication trans-mission,there remains a critical need for tunable terahertz(THz)devices with multi-channel in 5G/6G communication systems.A magnetic phase-coding meta-atom(MPM)is formed by the heterogeneous integration of La:YIG magneto-optical(MO)materials and Si microstructures.The MPM couples the magnetic induction phase of spin states with the propagation phase and can simultaneously satisfy the required output phase for dual frequencies under various external magnetic fields to realize the dynamic beam steering among multiple channels at 0.25 and 0.5 THz.The energy ratio of the target direction can reach 96.5%,and the nonreciprocal one-way transmission with a max isolation of 29.8 dB is realized due to the nonreciprocal phase shift of the MO layer.This nonreciprocal mechanism of magnetic induction reshaping of wavefront significantly holds promise for advancing integrated multi-functional THz devices with the characteristics of low-crosstalk,multi-channel,and multi-frequency,and has great potential to promote the development of THz large-capacity and high-speed communication.
基金supported by the National Key R&D Program of China(Grant No.2022YFA1402802)the National Natural Science Foundation of China(Grant Nos.12374103,12434003,and 12074057)。
文摘We theoretically demonstrate that multipartite entanglement and one-way Einstein-Podolsky-Rosen(EPR)steering in a magnon frequency comb(MFC)can be generated in a hybrid magnon-skyrmion system.When the system is driven by two microwave fields at the magnonic whispering gallery mode(m WGM)and the skyrmion,the skyrmion can be simultaneously entangled with three magnon modes of the MFC and the entanglement of the first-order magnon pair in the MFC also appears.The results show that the perfect one-way steering between the skyrmion and the three magnons can be obtained.Interestingly,the steering direction can be manipulated by controlling the amplitudes of two drive fields,which provides flexibility in controlling the asymmetry of the EPR steering and may well have practical applications.Moreover,the genuine tripartite entanglement among the skyrmion and the first-order magnon pair can be achieved with appropriate parameters in the steady state.Our work exhibits that the MFC has great potential in preparing multi-mode entanglement resources,with promising applications in quantum communication.
基金Project supported by the National Natural Science Foundation of China (Grant No. 12204440)Fundamental Research Program of Shanxi Province (Grant Nos. 20210302123063 and 202103021223184)。
文摘We introduce a novel scheme for achieving quantum entanglement and Einstein–Podolsky–Rosen(EPR) steering between an atomic ensemble and a mechanical oscillator within a hybrid atom–optomechanical system. The system comprises an optical cavity, a two-level atomic ensemble and a mechanical resonator that possesses Duffing nonlinearity. The interaction between these components is mediated by the cavity mode, which is driven by an external laser. Our findings indicate that optimizing the coupling strengths between photons and phonons, as well as between atoms and the cavity,leads to maximal entanglement and EPR steering. The amplitude of the driving laser plays a pivotal role in enhancing the coupling between photons and phonons, and the system maintains robust entanglement and EPR steering even under high dissipation, thereby mitigating the constraints on initial conditions and parameter precision. Remarkably, the Duffing nonlinearity enhances the system's resistance to thermal noise, ensuring its stability and entanglement protection. Our analysis of EPR steering conditions reveals that the party with lower dissipation exhibits superior stability and a propensity to steer the party with higher dissipation. These discoveries offer novel perspectives for advancing quantum information processing and communication technologies.
文摘President Xi Jinping’s APEC trip underscores China’s resolve to advance openness,cooperation,and shared prosperity across the Asia-Pacific region.FROM October 30 to November 1,2025,Chinese President Xi Jinping traveled to the Republic of Korea(ROK)to attend the 32nd Asia-Pacific Economic Cooperation(APEC)Economic Leaders’Meeting and also pay a state visit to the country.
基金supported by Guangxi Science and Technology Major Program(No.AA23073008)Hubei Key Laboratory of Water System Science for Sponge City Construction(Wuhan University)(No.2023–05)Nanning Innovation and Entrepreneur Leading Talent Project(No.2021001).
文摘The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated catalytic activity and minimal energy consumption continues to pose a significant challenge.In this research,Fluorine-doped copper-carbon(F/Cu-GAC)particle electrodes were effectively synthesized through an impregnationcalcination technique,utilizing granular activated carbon as the carrier and fluorinedoped modified copper oxides as the catalytic agents.The particle electrodes were subsequently utilized to promote the degradation of 2,4,6-trichlorophenol(2,4,6-TCP)in a threedimensional electrocatalytic reactor(3DER).The F/Cu-GAC particle electrodes were polarized under the action of electric field,which promoted the heterogeneous Fenton-like reaction in which H2O2 generated by two-electron oxygen reduction reaction(2e-ORR)of O_(2) was catalytically decomposed to·OH.The 3DER equipped with F/Cu-GAC particle electrodes showed 100%removal of 2,4,6-TCP and 79.24%removal of TOC with a specific energy consumption(EC)of approximately 0.019 kWh/g·COD after 2 h of operation.The F/Cu-GAC particle electrodes exhibited an overpotential of 0.38 V and an electrochemically active surface area(ECSA)of 715 cm^(2),as determined through linear sweep voltammetry(LSV)and cyclic voltammetry(CV)assessments.These findings suggest a high level of electrocatalytic performance.Furthermore,the catalytic mechanism of the 3DER equipped with F/Cu-GAC particle electrodes was elucidated through the application of X-ray photoelectron spectroscopy(XPS),electron spin resonance(ESR),and active species capture experiments.This investigation offers a novel approach for the effective degradation of 2,4,6-TCP.
基金Supported by the National Natural Science Foundation of China(52172324)Key Research and Development Plan of Shaanxi Province(2021GY-285,2021SF-483)+1 种基金Science and Technology Project of Shaanxi Provincial Department of Transport(21-20K,20-38T)Fundamental Research Funds for the Central Universities,CHD(300102323501)。
文摘In order to enhance the safety of autonomous driving vehicles,this work focuses on the issue of automatic-to-manual mode transition in the column electric power steering(C-EPS)system.First,we utilized an extended state observer to estimate the driver's steering torque and designed a steering mode transition unit.Second,we validated the mode switching function through an experimental platform.The results indicated that when using the extended state observer for torque estimation,the steering wheel angle and lower input angle errors were approximately±0.5%.The input and observed torque curves were closely aligned,demonstrating excellent tracking capability of the system.In addition,by adopting a steering mode conversion unit,the switch from autonomous control to manual control has been obtained,achieving a smooth and minimal change in steering wheel angle without significant bumps.The experimental results demonstrate that the designed mode switching strategy has the advantages of speed and smoothness,and has strong practical value.
基金Supported by National Natural Science Foundation of China(Grant Nos.U22A20246,52372382)Hefei Municipal Natural Science Foundation(Grant No.2022008)+1 种基金the Open Fund of State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures(Grant No.KF2023-06)S&T Program of Hebei(Grant No.225676162GH).
文摘In the parallel steering coordination control strategy for path tracking,it is difficult to match the current driver steering model using the fixed parameters with the actual driver,and the designed steering coordination control strategy under a single objective and simple conditions is difficult to adapt to the multi-dimensional state variables’input.In this paper,we propose a deep reinforcement learning algorithm-based multi-objective parallel human-machine steering coordination strategy for path tracking considering driver misoperation and external disturbance.Firstly,the driver steering mathematical model is constructed based on the driver preview characteristics and steering delay response,and the driver characteristic parameters are fitted after collecting the actual driver driving data.Secondly,considering that the vehicle is susceptible to the influence of external disturbances during the driving process,the Tube MPC(Tube Model Predictive Control)based path tracking steering controller is designed based on the vehicle system dynamics error model.After verifying that the driver steering model meets the driver steering operation characteristics,DQN(Deep Q-network),DDPG(Deep Deterministic Policy Gradient)and TD3(Twin Delayed Deep Deterministic Policy Gradient)deep reinforcement learning algorithms are utilized to design a multi-objective parallel steering coordination strategy which satisfies the multi-dimensional state variables’input of the vehicle.Finally,the tracking accuracy,lateral safety,human-machine conflict and driver steering load evaluation index are designed in different driver operation states and different road environments,and the performance of the parallel steering coordination control strategies with different deep reinforcement learning algorithms and fuzzy algorithms are compared by simulations and hardware in the loop experiments.The results show that the parallel steering collaborative strategy based on a deep reinforcement learning algorithm can more effectively assist the driver in tracking the target path under lateral wind interference and driver misoperation,and the TD3-based coordination control strategy has better overall performance.
基金Sponsored by the Project of Sichuan Landscape and Recreation Research Center(JGYQ2020037).
文摘In this study,CiteSpace software is used to carry out visual analysis on the three-dimensional research literature on urban recreation space from the perspective of compact city theory in the past 20 years,exploring the scientific development trend and research hotspots in this field.The results show that the number of published documents shows a fluctuating upward trend,and the significant growth rate reflects the role of policy orientation in promoting the concept of compact city.The co-occurrence analysis of keywords reveals the research hotspots of“compact city”,“recreation space”and“urban park”,while the emergence of new keywords such as“vertical city”and“spatial justice”indicates the new trend of recent research.The cluster analysis and timeline map further show the evolution of research themes,with“compact city”being the largest cluster and having rich connections with other themes such as“urban design”and“urban park”.
基金supported by the National Natural Science Foundation of China to Jiping Huang(12035004 and 12320101004)the Innovation Program of the Shanghai Municipal Education Commission to Jiping Huang(2023ZKZD06)+2 种基金the National Natural Science Foundation of China to Ying Li(92163123 and 52250191)the Zhejiang Provincial Natural Science Foundation of China to Ying Li(LZ24A050002)the National Natural Science Foundation of China to Liujun Xu(12375040,12088101,and U2330401).
文摘Thermal metamaterial represents a groundbreaking approach to control heat conduction,and,as a crucial component,thermal invisibility is of utmost importance for heat management.Despite the flourishing development of thermal invisibility schemes,they still face two limitations in practical applications.First,objects are typically completely enclosed in traditional cloaks,making them difficult to use and unsuitable for objects with heat sources.Second,although some theoretical proposals have been put forth to change the thermal conductivity of materials to achieve dynamic invisibility,their designs are complex and rigid,making them unsuitable for large-scale use in real threedimensional(3D)spaces.Here,we propose a concept of a thermal dome to achieve 3D invisibility.Our scheme includes an open functional area,greatly enhancing its usability and applicability.It features a reconfigurable structure,constructed with simple isotropic natural materials,making it suitable for dynamic requirements.The performance of our reconfigurable thermal dome has been confirmed through simulations and experiments,consistent with the theory.The introduction of this concept can greatly advance the development of thermal invisibility technology from theory to engineering and provide inspiration for other physical domains,such as direct current electric fields and magnetic fields.
基金Supported by the Zhejiang Medical Science and Technology Project,No.2022KY1325 and No.2023KY381Public Welfare Project of Jinhua Science and Technology Plan,No.2023-4-084Major Project of Jinhua Science and Technology Plan,No.2023-3-066.
文摘BACKGROUND Ganglioneuroma is a rare,well-differentiated,slow-growing benign tumor of the peripheral nerves,with surgical resection being the only curative treatment.Surgical resection of ganglioneuromas encasing major blood vessels remains a substantial clinical challenge.Traditionally,these cases often require open abdominal surgery or combined organ resections,and in some instances,the tumors are considered unresectable.Currently,no reports have described the resection of such tumors via laparoscopy.CASE SUMMARY A 35-year-old woman was admitted to our hospital after the incidental discovery of a retroperitoneal space-occupying lesion.Imaging revealed a mass with the celiac axis and superior mesenteric artery passing through it.A neurogenic tumor was suspected,with ganglioneuroma being the most likely diagnosis.Following comprehensive preoperative preparation,the retroperitoneal tumor was resected using a three-dimensional laparoscopy combined with an organ suspension technique.The surgical approach involved incising the tumor along the vascular axis and conducting meticulous,vascular-preserving tumor excision.The operation lasted approximately 458 minutes,with an estimated blood loss of 50 mL.The patient was discharged on the 8th postoperative day.A transient liver injury occurred after surgery but improved rapidly.After 11 months of postoperative follow-up,no complications or tumor recurrence were observed.CONCLUSION This case illustrates the feasibility of minimally invasive laparoscopic resection for retroperitoneal ganglioneuromas encasing major blood vessels.
