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Research on the Active and Passive Motion Characteristics of Bioinspired Soft Actuators
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作者 Qi Shen Jinzhu Zhang +2 位作者 Xiaoyan Xiong Hongjie Du Shiyu Li 《Journal of Bionic Engineering》 2026年第1期139-158,共20页
The soft actuator is characterized by high safety,flexibility,and adaptability.It is capable of both active and passive defor-mations.This paper presents a discrete degree of freedom(DOF)method for soft actuators to r... The soft actuator is characterized by high safety,flexibility,and adaptability.It is capable of both active and passive defor-mations.This paper presents a discrete degree of freedom(DOF)method for soft actuators to reveal DOF characteristics.The method draws on the superposition mechanism of the deformation characteristics of the sarcomere in the skeletal muscles of living organisms.Firstly,the multi-DOF deformation characteristics of the soft actuator are discretized into superimposed combinations of single-DOF micro-units.Then,the soft actuator was determined to contain deformation characteristics such as extension-contraction,bending,and twisting.Eighteen types of micro-units with basic deforma-tion characteristics were obtained depending on the axis and orientation.Further,the mapping relationship between the combination of micro-units and the motion characteristics of the soft actuator based on the GF set theory was established.Finally,an active-passive DOF co-structured soft actuator(APCSA)was developed.The graphical approach analyzes the experimental results,and it can be concluded that active and passive DOFs can coexist in the composite deformation of the soft actuator. 展开更多
关键词 Soft actuator active and passive DOF characteristics active and passive motion characteristics Micro-units G_(F)Set
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Prescribed-Time Active Disturbance Rejection Control for Electromagnetic Formation Flight Under Model Uncertainties and Disturbances
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作者 SHEN Xixi MENG Bin HU Jiangping 《空间控制技术与应用(中英文)》 北大核心 2026年第1期94-102,共9页
This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relativ... This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relative motion dynamics model,a prescribed time output feedback control strategy is proposed.A prescribed-time extended state observer is designed to estimate the relative velocity and external disturbances.The disturbance estimates are then used as the feedforward component of the controller.Building on this framework,a novel prescribed-time active disturbance rejection control strategy for position tracking is developed via a backstepping control design.The convergence of the extended state observer and the stability of the closed-loop system are rigorously analyzed using Lyapunov stability theory.Numerical simulations are performed to validate the effectiveness of the proposed controller. 展开更多
关键词 electromagnetic formation prescribed time active disturbance rejection control output feedback control
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Early intelligent active assistance in walking for hemiplegic patients under suspension protection: a randomized controlled trial
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作者 Ma Shanxin Zheng Jianling +5 位作者 Cheng Jian Lin Xi Li Qiuyuan Wang Li Zeng Yangkang Song Luping 《中国组织工程研究》 北大核心 2026年第12期3075-3082,共8页
BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking rec... BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function. 展开更多
关键词 hemiplegia stroke suspension protection system personal assistant machine intelligent walking aid early rehabilitation active training walking function NEUROPLASTICITY gait analysis motor function recovery rehabilitation training balance ability
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Comparative Risk of Stroke Associated with Active Smoking in Chinese and Asian Populations
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作者 Zemin Cai Xiaojing Guo +3 位作者 Xiao Zhang Danying Li Xiaoyue Li Xia Wan 《Biomedical and Environmental Sciences》 2026年第1期60-72,共13页
Objective Stroke is the third leading cause of death worldwide,with the highest incidence in Asia,particularly in China,where smoking remains a major risk factor.The smoking prevalence in China is similar to that in A... Objective Stroke is the third leading cause of death worldwide,with the highest incidence in Asia,particularly in China,where smoking remains a major risk factor.The smoking prevalence in China is similar to that in Asia.Whether the risk estimates for smoking-related stroke in China and all Asian countries are still unknown which is worth evaluating.Thus,this study aims to compare the Relative Risk(RR)of smoking-attributed stroke among the Chinese and Asian populations.Methods A literature search was conducted from the inception to September 10,2022.Studies meeting the criteria were included.The articles were screened,and related information was extracted.Pooled RRs stratified by smoking status and sex were analyzed,including subgroup analyses for China,other Asian countries,and Asia overall.Finally,publication bias and sensitivity analyses were conducted.Results Thirty-seven articles on the Chinese population and 15 on other Asian populations were included,with a mean Newcastle-Ottawa scale(NOS)score of 7.25.About ever smokers,there had no statistical difference existed in both sexes and females between China and other Asian countries,while the RR of males in other Asian countries[2.31(1.38,3.86)]was higher than that in China[1.21(1.15,1.26)];further subgroup analysis indicated that other Asian countries had higher RR[3.76(3.02,4.67)]in the morbidity subgroup.The RRs of both sexes,males and females,between China and the whole of Asia were not statistically different.As for current and former smokers,no meaningful statistical difference was observed in the pooled RRs of both sexes,males and females,in China,other Asian countries,and all of Asia.Conclusion The RR of males ever smokers in China was smaller than that in other Asian countries due to the few articles of morbidity subgroup,but had no statistical difference with the whole of Asia;other groups of ever smokers,current smokers,and former smokers were not statistically significant with other Asian countries or the whole of Asia. 展开更多
关键词 active smoking STROKE China Asian countries META-ANALYSIS
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A review of the pharmacology of active ingredients in Ginseng Radix et Rhizoma(Renshen)anti-aging
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作者 Tian-Yuan Liu Jin-Ning Chang +6 位作者 Xiao-Wei Dai Hao-Xin Ma Wei-Jia Chen Rui Du Akmal Muhammad Jian-Ming Li Zhong-Mei He 《Traditional Medicine Research》 2026年第3期65-76,共12页
Population aging is one of the common challenges in the current world.As people age,the body’s tissues including cells,and molecules inevitably degrade,and their functions gradually decline,causing various age-relate... Population aging is one of the common challenges in the current world.As people age,the body’s tissues including cells,and molecules inevitably degrade,and their functions gradually decline,causing various age-related diseases like Alzheimer’s disease,osteoporosis,low immunity,glucose and lipid metabolism disorders,and cardiovascular diseases.With the continuous increase of the elderly population,the pressure on the medical industry is increasing.To lower the burden on the medical industry and increase the average age of the elderly,it is vital to explore effective anti-aging materials.Ginseng Radix et Rhizoma(Renshen),as a traditional and precious Chinese medicinal herb,is known as the“king of all herbs”.It is famous for its effects of“tonifying Qi,restoring pulse”(helping with the generation of Qi(the fundamental,vital energy that continuously flows within the body)and the circulation of blood)and strengthening the body,nourishing the spleen and lungs,generating fluids and nourishing blood,calming the mind and improving intelligence.Recently,its anti-aging effect has received increasing attention from modern scientific research.This study summarizes the pharmacological effects of the main active ingredients of Renshen(ginsenosides,polysaccharides,etc.)on resisting aging,including preventing neuroaging,suppressing skin aging,mitigating ovarian aging,inhibiting osteoporosis and arthritis,enhancing the immune system of the elderly,protecting the cardiovascular system,resisting aging-induced fatigue and exerting the anti-tumor effects.Through network pharmacology and molecular docking,the anti-aging active ingredients of Renshen were screened,and the key targets and pathways of anti-aging active ingredients in Renshen were determined.Using network pharmacology,totally 106 drug targets and 3,479 disease targets were screened,and 79 common targets between aging and Renshen were identified.Three core targets were identified in the PPI network,including TNF,AKT1,and IL-1β.Molecular docking was used to obtain further verification.This study emphasizes the potential of Renshen as a source of anti-aging activity,which can be developed into a novel drug for the treatment of age-related diseases. 展开更多
关键词 Renshen active ingredients ANTI-AGING pharmacological effects network pharmacology molecular docking
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Photoelectrocatalytic degradation of refractory organic pollutants in water:Mechanism of active species generation by modulating the photoanode micro-interface
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作者 Yuhao Ma Yufei Zhou +4 位作者 Hongli Li Cheng Fang Mingchuan Yu Shaoxia Yang Junfeng Niu 《Chinese Chemical Letters》 2026年第1期198-207,共10页
The escalating global issues of water scarcity and pollution emphasize the critical need for the rapid development of efficient and eco-friendly water treatment technologies.Photoelectrocatalytic technology has emerge... The escalating global issues of water scarcity and pollution emphasize the critical need for the rapid development of efficient and eco-friendly water treatment technologies.Photoelectrocatalytic technology has emerged as a promising solution for effectively degrading refractory organic pollutants in water under light conditions.This review delves into the advancements made in the field,focusing on strategies to enhance the generation of active species by modulating the micro-interface of the photoanode.Strategies,such as morphological control,element doping,introduction of surface oxygen vacancies,and construction of heterostructures,significantly improve the separation efficiency of photogenerated charges and the generation of active species,thereby boosting the efficiency of photoelectrocatalytic performance.Furthermore,the review explores the potential applications of photoelectrocatalytic technology in organic pollutant degradation in solutions.It also outlines the current challenges and future development directions.Despite its remarkable laboratory success,practical implementation of photoelectrocatalytic technology encounters obstacles related to stability,cost-effectiveness,and operational efficiency.Future investigations need to focus on optimizing the performance of photoelectrocatalytic materials and exploring strategies for upscaling their application in real water treatment scenarios. 展开更多
关键词 Photoelectrocatalytic degradation PHOTOANODE Interface modulation active species MECHANISM
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An adaptive active vibration suppression method for diverse wind tunnel aircraft models
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作者 Mengde ZHOU Chenjin SUN +4 位作者 Qi ZHAO Binkai ZHU Wei WU Yuhang REN Wei LIU 《Chinese Journal of Aeronautics》 2026年第1期370-384,共15页
Under the condition of frequent replacement of wind tunnel models,multiple types of wind tunnel models are fixed by a slender support sting with low stiffness damping.When excited by wind load,various models produce r... Under the condition of frequent replacement of wind tunnel models,multiple types of wind tunnel models are fixed by a slender support sting with low stiffness damping.When excited by wind load,various models produce random multi-dimensional vibration with different characteristics,which makes it impossible to obtain accurate and efficient aerodynamic data.Therefore,in order to ensure the reliable and efficient conduction of wind tunnel test,a wind-tunnel-modeladaptive vibration control method is proposed in this paper.First,the split type adaptive vibration suppression structure is designed.Second,the multi-dimensional vibration characteristic characterization method is derived and the vibration characteristic identification method of the system is designed.Then,a vibration state estimation model is established according to the identification results of vibration characteristics,and a multi-actuator cooperative control method based on vibration state estimation is constructed.Finally,a model-adaptive vibration control system is built,and vibration characteristics identification and hammer experiments are carried out for two types of typical models.The results show that the proposed model-adaptive vibration control method increases the equivalent damping ratio of pitch and yaw dimensions of the high-aspect-ratio class model by 8.19 times and 48.81 times,respectively.The equivalent damping ratio of pitch and yaw dimensions of the highslenderness-ratio class model is increased by 16.44 and 5.43 times,respectively.It provides a strong guarantee for the reliable and efficient development of multi-type wind tunnel test tasks. 展开更多
关键词 active damping Model support system Vibration characteristic identification Vibration control Vibration state estimation Wind tunnels
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αionizing particle radiation detection and damage compensation methods for CMOS active pixel sensors
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作者 Shou-Long Xu Cui-Yue Wei +4 位作者 Zhi-Wei Qin Shu-Liang Zou Yong-Chao Han Qing-Yang Wei You-Jun Huang 《Nuclear Science and Techniques》 2026年第4期115-126,共12页
In this study,the mechanism and characteristics of the responseαparticles and the damage caused by them in CMOS active pixel(APS)sensors were investigated.A detection and compensation algorithm for dead pixels caused... In this study,the mechanism and characteristics of the responseαparticles and the damage caused by them in CMOS active pixel(APS)sensors were investigated.A detection and compensation algorithm for dead pixels caused byαparticle ionizing radiation was proposed,and the effects of dead-pixel compensation algorithms were compared and analyzed under different parameter conditions.The experimental results show thatαparticle response signal has highest accuracy at 9 dB gain,with an obvious“target-ring”distribution.With increasing cumulative dose,the CMOS APS pedestal tends to saturation while dead pixels continue increasing.Though some pixel damage recovers through natural annealing,the dead-to-noise ratio increases with irradiation time,reaching 32.54%after 72 h.A hierarchical clustering dead-pixel detection method is proposed,categorizing pixels into two types:those within and outside the response event.A classification compensation strategy combining mean and majority filtering is proposed.This compensation algorithm can address dead-pixel interference without affectingαparticle radiation response data.When iterated multiple times and with integration time exceeding 6.31 ms,the number of dead pixels can be effectively reduced. 展开更多
关键词 CMOS active pixel sensor αparticles Response event Radiation damage Dead-pixel compensation
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Feasibility of water vapor thermal therapy for treating lower urinary tract symptoms in men with localized prostate cancer on active surveillance:a case series
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作者 Mustufa Babar Farooz Babar +2 位作者 Noah Hawks-Ladds Justin Loloi Michael Ciatto 《The Canadian Journal of Urology》 2026年第1期193-199,共7页
Background:Prostate cancer is a common malignancy,with many men on active surveillance for localized,low-risk disease also experiencing lower urinary tract symptoms(LUTS)from benign prostatic hyperplasia(BPH).Water Va... Background:Prostate cancer is a common malignancy,with many men on active surveillance for localized,low-risk disease also experiencing lower urinary tract symptoms(LUTS)from benign prostatic hyperplasia(BPH).Water Vapor Thermal Therapy(WVTT)is a minimally invasive BPH treatment,but its safety and efficacy in this setting are unclear.Case Description:We report three men with localized PCa on active surveillance who underwent WVTT for LUTS.Conclusions:WVTT appears safe and potentially effective in treating LUTS,especially in those with lower-risk disease and smaller prostate volumes.Further research is needed to confirm safety,efficacy,and optimal patient selection. 展开更多
关键词 lower urinary tract symptoms benign prostatic hyperplasia prostatic neoplasms active surveillance case report
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Design and analysis of an augmented reduced-order active disturbance rejection control for nonlinear uncertain system
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作者 Kaiwen LIU Sen CHEN +1 位作者 Zhi-Liang ZHAO Wenchao XUE 《Science China(Technological Sciences)》 2026年第2期338-347,共10页
This paper proposes an augmented reduced-order active disturbance rejection control(ARADRC)to address the control challenges in nonlinear systems with unknown disturbances.An augmented reduced-order extended state obs... This paper proposes an augmented reduced-order active disturbance rejection control(ARADRC)to address the control challenges in nonlinear systems with unknown disturbances.An augmented reduced-order extended state observer(ARESO)is constructed to estimate the unmeasured states,the total disturbance,and its derivatives.Compared to conventional ESOs,the proposed ARESO can enhance the estimation performance by actively estimating the derivatives of the total disturbance.In the time domain,by an inductive decoupling-based bound analysis method,this paper rigorously investigates the closed-loop transient performance without the prior assumption on the boundedness of derivatives of nonlinear uncertainties.In the frequency domain,a comparative analysis demonstrates the superiority of ARADRC in both disturbance estimation and rejection.Finally,the magnetic levitation experiments validate the effectiveness of the proposed method. 展开更多
关键词 active disturbance rejection control extended state observer transient performance frequency domain analysis
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Throughput Maximization of Hybrid Active/Passive IRS-Assisted SWIPT System
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作者 HE Yingtong WU Yun 《Journal of Donghua University(English Edition)》 2026年第1期59-67,共9页
The integration of the intelligent reflecting surface(IRS)with simultaneous wireless information and power transfer(SWIPT)has emerged as a cost-effective and efficient solution to enhance the performance of informatio... The integration of the intelligent reflecting surface(IRS)with simultaneous wireless information and power transfer(SWIPT)has emerged as a cost-effective and efficient solution to enhance the performance of information and energy transfer.In this research,a hybrid active/passive IRS-assisted SWIPT system is proposed.Specifically,an active IRS(AIRS)and a passive IRS(PIRS)are deployed in the SWIPT system to facilitate a multiantenna base station(BS)in simultaneously delivering information and energy to multiple information users(IUs)and energy users(EUs).The objective is to maximize the sum throughput by jointly optimizing the transmitter beamforming and the reflection coefficient matrices of the AIRS and the PIRS while satisfying the transmitter power constraints,the energy harvesting(EH)requirements of EUs,and the AIRS amplification power limitations.However,the optimization variables are highly coupled and cannot be solved directly.To tackle this complex problem,we propose an efficient algorithm based on alternating optimization(AO)and semi-definite relaxation(SDR)techniques to obtain high-quality solutions.Simulation results demonstrate that the hybrid active/passive IRSassisted SWIPT system significantly enhances throughput performance and outperforms benchmark systems. 展开更多
关键词 simultaneous wireless information and power transfer(SWIPT) intelligent reflecting surface(IRS) hybrid active/passive IRS throughput optimization
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Pressure in active matter
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作者 Guo Yu Ruiyao Li +5 位作者 Fukang Li Jiayu Zhang Xiyue Li Zequ Chen Joscha Mecke Yongxiang Gao 《Chinese Physics B》 2025年第9期330-342,共13页
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
关键词 active matter active pressure equation of state active Brownian particles
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Research on Vibration Control of Pump Valve Pipeline System Based on Active Damping Device 被引量:1
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作者 Hao-zhe Zhu Li-dong He Qing-wang Qin 《风机技术》 2025年第2期78-83,共6页
Pump valve pipeline vibration brings serious safety hazards to the operation of the equipment,for the pump valve system in the process of variable flow,variable speed,variable openings lead to excessive pipeline vibra... Pump valve pipeline vibration brings serious safety hazards to the operation of the equipment,for the pump valve system in the process of variable flow,variable speed,variable openings lead to excessive pipeline vibration.An active damping device(ADD)is used to the vibration of the pump valve pipeline system to apply the control force,to achieve the active control of the pipeline vibration.A pump-valve pipeline vibration test bench was built to compare the control effect of active damping device on pipeline vibration under different pump valve working conditions,and the results show that applying ADD control could effectively suppress the vibration of the pump valve pipeline and enhance the stability of the equipment during operation.At different pump operating rotation frequencies,the vibration amplitude of the pump valve pipeline in working frequency and its multiple frequencies are also effectively suppressed,with the maximum amplitude reduction of more than 60%.For the valve vibration caused by different operating openings,the vibration of the highest reduction of 68%,and the centrifugal pump drive shaft vi-bration reduced by up to 73%,which provides a new idea for vibration control of pump valve pipeline system. 展开更多
关键词 active Damping Device active Control ACTUATOR Pump Valve Pipeline
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Reactive Power Optimization Model of Active Distribution Network with New Energy and Electric Vehicles 被引量:1
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作者 Chenxu Wang Jing Bian Rui Yuan 《Energy Engineering》 2025年第3期985-1003,共19页
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
关键词 active distribution network new energy electric vehicles dynamic reactive power optimization kmedoids clustering hybrid optimization algorithm
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Research Advances in the Control of Spider Mites Using Bioactive Substances of Biological Origin
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作者 Tongshu DAI Kaicheng LIU Yanjie LUO 《Asian Agricultural Research》 2025年第11期51-53,共3页
Spider mites are significant pests in agricultural production.The increasing resistance of spider mites,along with environmental pollution and ecological imbalance caused by their control,is primarily attributed to th... Spider mites are significant pests in agricultural production.The increasing resistance of spider mites,along with environmental pollution and ecological imbalance caused by their control,is primarily attributed to the long-term use of chemical acaricides in agriculture.In contrast,bioactive substances of biological origin offer advantages such as wide availability,environmental friendliness,and low tendency to induce resistance,making them a research hotspot for spider mite control.This review summarizes recent advances in the use of plant-derived active compounds(exemplified by extracts from Veratrum rhizomes),RNA interference(RNAi)technology,and microorganism-derived active substances for controlling spider mites.These bioactive agents exert acaricidal effects by disrupting the nervous system,interfering with metabolic processes,or silencing key genes in mites,demonstrating favorable efficacy and considerable potential for development.However,challenges remain,including poor environmental stability,slow action,high production costs,and insufficient understanding of their effects on non-target organisms.Therefore,future research should focus on the screening and development of novel bioactive substances of biological origin,elucidation of their mechanisms of action,optimization of formulation technologies,and assessment of their ecological safety.These efforts will provide valuable insights for promoting the advancement of bioactive substances and supporting sustainable agricultural development. 展开更多
关键词 Bioactive substances of BIOLOGICAL ORIGIN Spider MITE CONTROL RNA interference Plant-derived active substances Microorganism-derived active substances
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A hydrogen-centric perspective on electrocatalytic nitrate reduction:Managing the active hydrogen lifecycle from generation to utilization
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作者 Zhihao Wang Xu Zhang +1 位作者 Zhiyu Ren Zhimin Chen 《Journal of Energy Chemistry》 2025年第10期210-230,共21页
Electrocatalytic nitrate reduction reaction(NitRR)utilizing water as a hydrogen source under ambient conditions represents a highly promising avenue for sustainable ammonia synthesis and environmental remediation.Howe... Electrocatalytic nitrate reduction reaction(NitRR)utilizing water as a hydrogen source under ambient conditions represents a highly promising avenue for sustainable ammonia synthesis and environmental remediation.However,achieving high efficiency and selectivity in NitRR is fundamentally challenged by the complex lifecycle management of active hydrogen derived from water splitting.This review provides a timely and comprehensive analysis centered on the pivotal role and meticulous regulation of active hydrogen throughout the NitRR process.We first elucidate the distinct functions and characteristics of various hydrogen species,followed by a survey of advanced characterization techniques crucial for monitoring the dynamics of active hydrogen.Critically,three core strategies were systematically dissected to modulate the active hydrogen lifecycle:accelerating water activation and dissociation,enhancing the directional transport of hydrogen species,and precisely tuning active hydrogen coupling pathways while suppressing parasitic hydrogen evolution.By consolidating current understanding from both catalyst design and reaction mechanism perspectives,this review offers a hydrogen-centric roadmap and highlights emerging opportunities for rationally engineering advanced NitRR systems. 展开更多
关键词 Electrocatalytic nitrate reduction active hydrogen regulation Characterization methods Water activation and dissociation Promoting active hydrogen transfer Hydrogen evolution suppression
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Functional macrocyclic arenes with active binding sites inside cavity for biomimetic molecular recognition
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作者 Xixian Sun Shengke Li +1 位作者 Ruibing Wang Leyong Wang 《Chinese Chemical Letters》 2025年第4期1-2,共2页
Molecular recognition of bioreceptors and enzymes relies on orthogonal interactions with small molecules within their cavity. To date, Chinese scientists have developed three types of strategies for introducing active... Molecular recognition of bioreceptors and enzymes relies on orthogonal interactions with small molecules within their cavity. To date, Chinese scientists have developed three types of strategies for introducing active sites inside the cavity of macrocyclic arenes to better mimic molecular recognition of bioreceptors and enzymes.The editorial aims to enlighten scientists in this field when they develop novel macrocycles for molecular recognition, supramolecular assembly, and applications. 展开更多
关键词 supramolecular assembly orthogonal interactions introducing active sites active binding sites macrocyclic arenes molecular recognition orthogonal interactions small molecules biomimetic molecular recognition
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Adaptive Sliding Mode Control With Linear Extended State Observer for Active Magnetic Bearing-Rotor Systems
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作者 Yaozhong Zheng Hai-Tao Zhang +3 位作者 Ziheng Yu Xiang Huang Haichao Jiao Han Ding 《IEEE/CAA Journal of Automatica Sinica》 2025年第8期1736-1738,共3页
Dear Editor,Active magnetic bearings(AMBs)are of considerable interest and significance in smart manufacturing due to their zero-friction and adaptivity to noncontact rotor rotations.This paper proposes an active levi... Dear Editor,Active magnetic bearings(AMBs)are of considerable interest and significance in smart manufacturing due to their zero-friction and adaptivity to noncontact rotor rotations.This paper proposes an active levitation control algorithm based on adaptive sliding mode control(ASMC)equipped with linear extended state observer(LESO).Sufficient conditions are derived to guarantee the asymptotical stability of the associated closed-loop system.Experiments are conducted on a real AMB-rotor platform to demonstrate the effectiveness and superiority of the proposed algorithm. 展开更多
关键词 smart manufacturing linear extended state observer leso sufficient active magnetic bearing rotor systems adaptive sliding mode control magnetic bearings ambs adaptive sliding mode control asmc equipped active levitation control algorithm
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A Novel Feedforward Hybrid Active Noise Control System with Narrowband Frequency Adaptive Estimation and Error Separation
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作者 PANG Mingrui LIU Yifei LIU Jian 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第5期638-647,共10页
The conventional feedforward hybrid active noise control(FFHANC)system combines the advantages of the feedforward narrowband active noise control(FFNANC)system and the feedforward broadband active noise control(FFBANC... The conventional feedforward hybrid active noise control(FFHANC)system combines the advantages of the feedforward narrowband active noise control(FFNANC)system and the feedforward broadband active noise control(FFBANC)system.To enhance its adaptive adjustment capability under frequency mismatch(FM)conditions,this paper introduces a narrowband frequency adaptive estimation module into the conventional FFHANC system.This module integrates an autoregressive(AR)model and a linear cascaded adaptive notch filter(LCANF),enabling accurate reference signal frequency estimation even under significant FM.Furthermore,in order to improve the coherence between narrowband and broadband components in the system’s error signal and its corresponding control filter for the conventional FFHANC system,this paper proposes an algorithm based on autoregressive bandpass filter bank(AR-BPFB)for error separation.Simulation results demonstrate that the proposed FFHANC system maintains robust performance under high FM conditions and effectively suppresses hybrid-band noise.The AR-BPFB algorithm significantly elevates the convergence speed of the FFHANC system. 展开更多
关键词 active noise control feedforward hybrid active noise control(FFHANC)system autoregressive(AR)model linear cascaded adaptive notch filter(LCANF) bandpass filter bank(BPFB) error separation
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Active flow control in aeronautic field and disease treatment in medical field
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作者 Zhengyu ZUO Xin ZHANG 《Chinese Journal of Aeronautics》 2025年第11期1-4,共4页
Activeow control technology is a technique that controls the internaloweld of aircraft engines or theoweld around wings by means of disturbances induced by actuators,and adjusts the aerodynamic force and attitude of t... Activeow control technology is a technique that controls the internaloweld of aircraft engines or theoweld around wings by means of disturbances induced by actuators,and adjusts the aerodynamic force and attitude of the aircraft,so as to achieve the purposes of increasing lift,reducing drag,suppressing vibration and reducing noise.Hailed as an important source of innovative development for aircraft,this technology provides a new technical approach to solve the aerodynamic problems of aircraft,signicantly improve their comprehensive performance,break throughight boundaries,and promote disruptive innovation in the next generation of aircraft. 展开更多
关键词 aeronautical field disease treatment active flow control controls internaloweld adjusts aerodynamic force attitude aerodynamic problems activeow control technology aircraft engines
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