针对无监督环境下传统网络异常诊断算法存在异常点定位和异常数据分类准确率低等不足,通过设计一种基于改进Q-learning算法的无线网络异常诊断方法:首先基于ADU(Asynchronous Data Unit异步数据单元)单元采集无线网络的数据流,并提取数...针对无监督环境下传统网络异常诊断算法存在异常点定位和异常数据分类准确率低等不足,通过设计一种基于改进Q-learning算法的无线网络异常诊断方法:首先基于ADU(Asynchronous Data Unit异步数据单元)单元采集无线网络的数据流,并提取数据包特征;然后构建Q-learning算法模型探索状态值和奖励值的平衡点,利用SA(Simulated Annealing模拟退火)算法从全局视角对下一时刻状态进行精确识别;最后确定训练样本的联合分布概率,提升输出值的逼近性能以达到平衡探索与代价之间的均衡。测试结果显示:改进Q-learning算法的网络异常定位准确率均值达99.4%,在不同类型网络异常的分类精度和分类效率等方面,也优于三种传统网络异常诊断方法。展开更多
In clinical practice,antibiotics have historically been utilized for the treatment of pathogenic bacteria.However,the gradual emergence of antibiotic resistance among bacterial strains has posed a significant challeng...In clinical practice,antibiotics have historically been utilized for the treatment of pathogenic bacteria.However,the gradual emergence of antibiotic resistance among bacterial strains has posed a significant challenge to this approach.In 2022,Escherichia coli,a Gram-negative bacterium renowned for its widespread pathogenicity and high virulence,emerged as the predominant pathogenic bacterium in China.The rapid emergence of antibiotic-resistant E.coli strains has rendered antibiotics insufficient to fight E.coli infections.Traditional Chinese medicine(TCM)has made remarkable contributions to the health of Chinese people for thousands of years,and its significant therapeutic effects have been proven in clinical practice.In this paper,we provide a comprehensive review of the advances and mechanisms of TCM and its active ingredients against antibiotic-resistant E.coli infections.First of all,this review introduces the classification,antibiotic resistance characteristics and mechanisms of E.coli.Then,the TCM formulas and extracts are listed along with their active ingredients against E.coli,including extraction solution,minimum inhibitory concentration(MIC),and the antibacterial mechanisms.In addition,there is growing evidence supporting the synergistic therapeutic strategy of combining TCM with antibiotics for the treatment of antibiotic-resistant E.coli infections,and we provide a summary of this evidence and its underlying mechanisms.In conclusion,we present a comprehensive review of TCM and highlight its potential and advantages in the prevention and treatment of E.coli infections.We hold the opinion that TCM will play an important role in global health,pharmaceutical development,and livestock farming in the future.展开更多
Gallium nitride(GaN)single crystal with prominent electron mobility and heat resistance have great potential in the high temperature integrate electric power systems.However,the sluggish charge storage kinetics and in...Gallium nitride(GaN)single crystal with prominent electron mobility and heat resistance have great potential in the high temperature integrate electric power systems.However,the sluggish charge storage kinetics and inadequate energy densities are bottlenecks to its practical application.Herein,the self-supported GaN/Mn_(3)O_(4) integrated electrode is developed for both energy harvesting and storage under the high temperature environment.The experimental and theoretical calculations results reveal that such integrated structures with Mn-N heterointerface bring abundant active sites and reconstruct low-energy barrier channels for efficient charge transferring,reasonably optimizing the ions adsorption ability and strengthening the structural stability.Consequently,the assembled GaN based supercapacitors deliver the power density of 34.0 mW cm^(-2) with capacitance retention of 81.3%after 10000 cycles at 130℃.This work innovatively correlates the centimeter scale GaN single crystal with ideal theoretical capacity Mn_(3)O_(4) and provides an effective avenue for the follow-up energy storage applications of the wide bandgap semiconductor.展开更多
Permanent magnet synchronous motor based electro-mechanical actuation servo drives have widespread applications in the aviation field,such as unmanned aerial vehicle electric servos,electric cabin doors,and mechanical...Permanent magnet synchronous motor based electro-mechanical actuation servo drives have widespread applications in the aviation field,such as unmanned aerial vehicle electric servos,electric cabin doors,and mechanical arms.The performance of the servo drive,which encompasses the response to the torque,efficiency,control bandwidth and the steady-state positioning accuracy,significantly influences the performance of the aviation actuation.Consequently,enhancing the control bandwidth and refining the positioning accuracy of aviation electro-mechanical actuation servo drives have emerged as a focal point of research.This paper investigates the multi-source disturbances present in aviation electro-mechanical actuation servo systems and summarizes recent research on high-performance servo control methods based on active disturbance rejection control(ADRC).We present a comprehensive overview of the research status pertaining to servo control architecture,strategies for suppressing disturbances in the current loop,and ADRC-based strategies for the position loop.We delineate the research challenges and difficulties encountered by aviation electro-mechanical actuation servo drive control technology.展开更多
Considering the uncertainty of grid connection of electric vehicle charging stations and the uncertainty of new energy and residential electricity load,a spatio-temporal decoupling strategy of dynamic reactive power o...Considering the uncertainty of grid connection of electric vehicle charging stations and the uncertainty of new energy and residential electricity load,a spatio-temporal decoupling strategy of dynamic reactive power optimization based on clustering-local relaxation-correction is proposed.Firstly,the k-medoids clustering algorithm is used to divide the reduced power scene into periods.Then,the discrete variables and continuous variables are optimized in the same period of time.Finally,the number of input groups of parallel capacitor banks(CB)in multiple periods is fixed,and then the secondary static reactive power optimization correction is carried out by using the continuous reactive power output device based on the static reactive power compensation device(SVC),the new energy grid-connected inverter,and the electric vehicle charging station.According to the characteristics of the model,a hybrid optimization algorithm with a cross-feedback mechanism is used to solve different types of variables,and an improved artificial hummingbird algorithm based on tent chaotic mapping and adaptive mutation is proposed to improve the solution efficiency.The simulation results show that the proposed decoupling strategy can obtain satisfactory optimization resultswhile strictly guaranteeing the dynamic constraints of discrete variables,and the hybrid algorithm can effectively solve the mixed integer nonlinear optimization problem.展开更多
The dwell scheduling problem for a multifunctional radar system is led to the formation of corresponding optimiza-tion problem.In order to solve the resulting optimization prob-lem,the dwell scheduling process in a sc...The dwell scheduling problem for a multifunctional radar system is led to the formation of corresponding optimiza-tion problem.In order to solve the resulting optimization prob-lem,the dwell scheduling process in a scheduling interval(SI)is formulated as a Markov decision process(MDP),where the state,action,and reward are specified for this dwell scheduling problem.Specially,the action is defined as scheduling the task on the left side,right side or in the middle of the radar idle time-line,which reduces the action space effectively and accelerates the convergence of the training.Through the above process,a model-free reinforcement learning framework is established.Then,an adaptive dwell scheduling method based on Q-learn-ing is proposed,where the converged Q value table after train-ing is utilized to instruct the scheduling process.Simulation results demonstrate that compared with existing dwell schedul-ing algorithms,the proposed one can achieve better scheduling performance considering the urgency criterion,the importance criterion and the desired execution time criterion comprehen-sively.The average running time shows the proposed algorithm has real-time performance.展开更多
Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active...Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active centers influencing the rate of both methanol and CO formation.The particle size and the interaction between Cu and the support materials are influenced by the coprecipitation conditions,let alone that the mechanistic divergence remains unclear.In this work,a series of Cu/ZnO/ZrO_(2) catalysts were prepared via co-precipitation at different pH value and systematically characterized.The structure has been correlated with kinetic results to establish the structure-performance relationship.Kinetic analysis demonstrates that methanol synthesis follows a single-site Langmuir-Hinshelwood(L-H)mechanism,i.e.,Cu serves as the active site where CO_(2) and H_(2) competitively adsorb and react to form methanol.In contrast,CO formation proceeds via a dual-site L-H mechanism,where CO_(2) adsorbs onto ZnO and H_(2) onto Cu,with the reaction occurring at the Cu/ZnO interface.Therefore,for the direct formation of methanol,solely reducing the particle size of Cu would not be beneficial.展开更多
In the last decade,the study of pressure in active matter has attracted growing attention due to its fundamental relevance to nonequilibrium statistical physics.Active matter systems are composed of particles that con...In the last decade,the study of pressure in active matter has attracted growing attention due to its fundamental relevance to nonequilibrium statistical physics.Active matter systems are composed of particles that consume energy to sustain persistent motion,which are inherently far from equilibrium.These particles can exhibit complex behaviors,including motility-induced phase separation,clustering,and anomalous stress distributions,motivating the introduction of active swim stress and swim pressure.Unlike in passive fluids,pressure in active systems emerges from momentum flux originating from swim force rather than equilibrium conservative interactions,offering a distinct perspective for understanding their mechanical response.Simple models of active Brownian particles(ABPs)have been employed in theoretical and simulation studies across both dilute and dense regimes,revealing that pressure is a state function and exhibits a nontrivial dependence on density.Together with nonequilibrium statistical concepts such as effective temperature and effective adhesion,pressure offers important insight for understanding behaviors in active matter such as sedimentation equilibrium and motility induced phase separation.Extensions of ABP models beyond their simplest form have underscored the fragility of the pressure-based equation of state,which can break down under factors such as density-dependent velocity,torque,complex boundary geometries and interactions.Building on these developments,this review provides a comprehensive survey of theoretical and experimental advances,with particular emphasis on the microscopic origins of active pressure and the mechanisms underlying the breakdown of the equation of state.展开更多
文摘针对无监督环境下传统网络异常诊断算法存在异常点定位和异常数据分类准确率低等不足,通过设计一种基于改进Q-learning算法的无线网络异常诊断方法:首先基于ADU(Asynchronous Data Unit异步数据单元)单元采集无线网络的数据流,并提取数据包特征;然后构建Q-learning算法模型探索状态值和奖励值的平衡点,利用SA(Simulated Annealing模拟退火)算法从全局视角对下一时刻状态进行精确识别;最后确定训练样本的联合分布概率,提升输出值的逼近性能以达到平衡探索与代价之间的均衡。测试结果显示:改进Q-learning算法的网络异常定位准确率均值达99.4%,在不同类型网络异常的分类精度和分类效率等方面,也优于三种传统网络异常诊断方法。
基金supported by the Fundamental Research Funds for the Central Public Welfare Research Institutes,China(Grant Nos.:ZZ16-YQ-037,JIPY2023003,and JJPY2022022)China Academy of Chinese Medical Sciences(CACMS)Innovation Fund(Grant No.:CI2021A00601).
文摘In clinical practice,antibiotics have historically been utilized for the treatment of pathogenic bacteria.However,the gradual emergence of antibiotic resistance among bacterial strains has posed a significant challenge to this approach.In 2022,Escherichia coli,a Gram-negative bacterium renowned for its widespread pathogenicity and high virulence,emerged as the predominant pathogenic bacterium in China.The rapid emergence of antibiotic-resistant E.coli strains has rendered antibiotics insufficient to fight E.coli infections.Traditional Chinese medicine(TCM)has made remarkable contributions to the health of Chinese people for thousands of years,and its significant therapeutic effects have been proven in clinical practice.In this paper,we provide a comprehensive review of the advances and mechanisms of TCM and its active ingredients against antibiotic-resistant E.coli infections.First of all,this review introduces the classification,antibiotic resistance characteristics and mechanisms of E.coli.Then,the TCM formulas and extracts are listed along with their active ingredients against E.coli,including extraction solution,minimum inhibitory concentration(MIC),and the antibacterial mechanisms.In addition,there is growing evidence supporting the synergistic therapeutic strategy of combining TCM with antibiotics for the treatment of antibiotic-resistant E.coli infections,and we provide a summary of this evidence and its underlying mechanisms.In conclusion,we present a comprehensive review of TCM and highlight its potential and advantages in the prevention and treatment of E.coli infections.We hold the opinion that TCM will play an important role in global health,pharmaceutical development,and livestock farming in the future.
基金supported by NSFC(Grant No.52202265,52302004,52472010,62434010)the Taishan Scholars Program of Shandong Province(tsqn202306330)+1 种基金Shenzhen Science and Technology Program(JCYJ20230807094009018)Xiaomi Young Talents Program(2023XM06).
文摘Gallium nitride(GaN)single crystal with prominent electron mobility and heat resistance have great potential in the high temperature integrate electric power systems.However,the sluggish charge storage kinetics and inadequate energy densities are bottlenecks to its practical application.Herein,the self-supported GaN/Mn_(3)O_(4) integrated electrode is developed for both energy harvesting and storage under the high temperature environment.The experimental and theoretical calculations results reveal that such integrated structures with Mn-N heterointerface bring abundant active sites and reconstruct low-energy barrier channels for efficient charge transferring,reasonably optimizing the ions adsorption ability and strengthening the structural stability.Consequently,the assembled GaN based supercapacitors deliver the power density of 34.0 mW cm^(-2) with capacitance retention of 81.3%after 10000 cycles at 130℃.This work innovatively correlates the centimeter scale GaN single crystal with ideal theoretical capacity Mn_(3)O_(4) and provides an effective avenue for the follow-up energy storage applications of the wide bandgap semiconductor.
基金supported by the National Natural Science Foundation of China(Nos.52177059 and 52407064).
文摘Permanent magnet synchronous motor based electro-mechanical actuation servo drives have widespread applications in the aviation field,such as unmanned aerial vehicle electric servos,electric cabin doors,and mechanical arms.The performance of the servo drive,which encompasses the response to the torque,efficiency,control bandwidth and the steady-state positioning accuracy,significantly influences the performance of the aviation actuation.Consequently,enhancing the control bandwidth and refining the positioning accuracy of aviation electro-mechanical actuation servo drives have emerged as a focal point of research.This paper investigates the multi-source disturbances present in aviation electro-mechanical actuation servo systems and summarizes recent research on high-performance servo control methods based on active disturbance rejection control(ADRC).We present a comprehensive overview of the research status pertaining to servo control architecture,strategies for suppressing disturbances in the current loop,and ADRC-based strategies for the position loop.We delineate the research challenges and difficulties encountered by aviation electro-mechanical actuation servo drive control technology.
基金funded by the“Research and Application Project of Collaborative Optimization Control Technology for Distribution Station Area for High Proportion Distributed PV Consumption(4000-202318079A-1-1-ZN)”of the Headquarters of the State Grid Corporation.
文摘Considering the uncertainty of grid connection of electric vehicle charging stations and the uncertainty of new energy and residential electricity load,a spatio-temporal decoupling strategy of dynamic reactive power optimization based on clustering-local relaxation-correction is proposed.Firstly,the k-medoids clustering algorithm is used to divide the reduced power scene into periods.Then,the discrete variables and continuous variables are optimized in the same period of time.Finally,the number of input groups of parallel capacitor banks(CB)in multiple periods is fixed,and then the secondary static reactive power optimization correction is carried out by using the continuous reactive power output device based on the static reactive power compensation device(SVC),the new energy grid-connected inverter,and the electric vehicle charging station.According to the characteristics of the model,a hybrid optimization algorithm with a cross-feedback mechanism is used to solve different types of variables,and an improved artificial hummingbird algorithm based on tent chaotic mapping and adaptive mutation is proposed to improve the solution efficiency.The simulation results show that the proposed decoupling strategy can obtain satisfactory optimization resultswhile strictly guaranteeing the dynamic constraints of discrete variables,and the hybrid algorithm can effectively solve the mixed integer nonlinear optimization problem.
基金supported by the National Natural Science Foundation of China(6177109562031007).
文摘The dwell scheduling problem for a multifunctional radar system is led to the formation of corresponding optimiza-tion problem.In order to solve the resulting optimization prob-lem,the dwell scheduling process in a scheduling interval(SI)is formulated as a Markov decision process(MDP),where the state,action,and reward are specified for this dwell scheduling problem.Specially,the action is defined as scheduling the task on the left side,right side or in the middle of the radar idle time-line,which reduces the action space effectively and accelerates the convergence of the training.Through the above process,a model-free reinforcement learning framework is established.Then,an adaptive dwell scheduling method based on Q-learn-ing is proposed,where the converged Q value table after train-ing is utilized to instruct the scheduling process.Simulation results demonstrate that compared with existing dwell schedul-ing algorithms,the proposed one can achieve better scheduling performance considering the urgency criterion,the importance criterion and the desired execution time criterion comprehen-sively.The average running time shows the proposed algorithm has real-time performance.
基金supported by Research Grant from China Petroleum and Chemical Corp。
文摘Cu/ZnO-based catalysts are widely employed for methanol synthesis via CO_(2) hydrogenation.The preparation procedure is sensitive to the particle size and interfacial structure,which are considered as potential active centers influencing the rate of both methanol and CO formation.The particle size and the interaction between Cu and the support materials are influenced by the coprecipitation conditions,let alone that the mechanistic divergence remains unclear.In this work,a series of Cu/ZnO/ZrO_(2) catalysts were prepared via co-precipitation at different pH value and systematically characterized.The structure has been correlated with kinetic results to establish the structure-performance relationship.Kinetic analysis demonstrates that methanol synthesis follows a single-site Langmuir-Hinshelwood(L-H)mechanism,i.e.,Cu serves as the active site where CO_(2) and H_(2) competitively adsorb and react to form methanol.In contrast,CO formation proceeds via a dual-site L-H mechanism,where CO_(2) adsorbs onto ZnO and H_(2) onto Cu,with the reaction occurring at the Cu/ZnO interface.Therefore,for the direct formation of methanol,solely reducing the particle size of Cu would not be beneficial.
基金financial support from the General Program of the National Natural Science Foundation of China(Grant No.12474195)the Key Project of Guangdong Provincial Department of Education(Grant No.2023ZDZX3021)the Natural Science Foundation of Guangdong Province(Grant No.2024A1515011343)。
文摘In the last decade,the study of pressure in active matter has attracted growing attention due to its fundamental relevance to nonequilibrium statistical physics.Active matter systems are composed of particles that consume energy to sustain persistent motion,which are inherently far from equilibrium.These particles can exhibit complex behaviors,including motility-induced phase separation,clustering,and anomalous stress distributions,motivating the introduction of active swim stress and swim pressure.Unlike in passive fluids,pressure in active systems emerges from momentum flux originating from swim force rather than equilibrium conservative interactions,offering a distinct perspective for understanding their mechanical response.Simple models of active Brownian particles(ABPs)have been employed in theoretical and simulation studies across both dilute and dense regimes,revealing that pressure is a state function and exhibits a nontrivial dependence on density.Together with nonequilibrium statistical concepts such as effective temperature and effective adhesion,pressure offers important insight for understanding behaviors in active matter such as sedimentation equilibrium and motility induced phase separation.Extensions of ABP models beyond their simplest form have underscored the fragility of the pressure-based equation of state,which can break down under factors such as density-dependent velocity,torque,complex boundary geometries and interactions.Building on these developments,this review provides a comprehensive survey of theoretical and experimental advances,with particular emphasis on the microscopic origins of active pressure and the mechanisms underlying the breakdown of the equation of state.
