检索结果-南通市图书馆

维普期刊数据库

A Novel Dual Helical Magnetorheological Fluid Micro-Robot

在线全文

学校读者我要写书评

暂无评论

Mechanical Engineering Science 2022年第1期4卷 35-42页

作者： Zhixiang LI minglu chi Shuaibing CHANG Xiaoyan QIAN Jiawen JIA Jianbo LI Chenyu WANG Zuhua GUO School of Intelligent Engineering Henan Institute of TechnologyHenan Xinxiang 453000China School of Electrical Engineering and Automation Henan Institute of TechnologyHenan Xinxiang 453000China School of Economics Henan Institute of TechnologyHenan Xinxiang 453000China College of Computer Science and Technology Henan Institute of TechnologyHenan Xinxiang 453000China

To address the problem of flexible drive control of gastrointestinal(GI)tract micro-capsule robot posture,a novel dual helix magnetorheological fluid(MRF)micro-robot(DHMRFMR)is proposed and developed in this paper.Based on the mechanical properties of magnetorheological fluid,the relationship model of magnetic field force is obtained,and the thrust model is established.Double micro DC deceleration motor is used to drive the two ends of the helical actuator to make the DHMRFMR forward and backward,by changing the external magnetic field rotation speed,direction and distance,adjust the attitude direction of the robot.Numerical simulation software ANSYS is used to analyze the motion law of external fluid of DHMRFMR,and the visualization of fluid velocity and pressure distribution is realized.The front-end helix actuator can change the flow path of the fluid,and the middle and tail of the DHMRFMR bear less pressure,which improves the stability and flexibility of the robot.The novel DHMRFMR is suitable for internal drive in bending environment,and has a good application prospect in biomedical engineering field in human intestinal unstructured environment.

关键词： Dual helical actuation Micro-robot Magnetorheological fluid Attitude control Simulated analysis

Design and motion control analysis of double helix wall climbing robot

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Mechanical Engineering Science 2022年第1期4卷 27-34页

作者： Jinzhan WANG minglu chi Yue MA Qinchao REN Mengqing HUANG Yibo CHEN Ruihua REN Jinyu WANG Si LIU School of Intelligent Engineering Henan Institute of TechnologyXinxiangHenan45300China School of Civil Engineering Harbin UniversityHarbin150086China Jiangsu Huibo Robot Technology Co.LTD Jiangsu Suzhou 215121China

For the detection environment of complex walls such as high-rise buildings,a double helix wall climbing robot(DHWCR)with strong adsorption force and good stability is designed and developed,which uses symmetrical propellers to provide adsorption force.The symmetrical driving structure can provide smooth thrust for the DHWCR,so that the robot can be absorbed to the wall surface with different roughness.A left and right control frame with multiple degrees of freedom is designed,which can adjust the fixed position of the brushless propeller motor in the front and back directions,realize the continuous adjustable thrust direction of the robot,and improve the flexibility of the robot movement.Using the front wheel steering mechanism with universal joint,the steering control of the DHWCR is realized by differential control.In the vertical to ground transition,the front and rear brushless motors can provide the pull up and oblique thrust,so that the DHWCR can smoothly transition to the vertical wall.The motion performance and adaptability of the DHWCR in the horizontal ground and vertical wall environment are tested.The results show that the DHWCR can switch motion between the horizontal ground and vertical wall,and can stably adsorb on the vertical wall with flexible attitude control.The DHWCR can move at a fast speed.The speed on the horizontal ground is higher than that on the vertical wall,which verifies the feasibility and reliability of the DHWCR moving stably on the vertical wall.

关键词： Double helix Wall climbing robot Reverse thrust adsorption Structural design Motion control

A Systematic Analysis of Early Life Exposure to the chinese Famine(1959-1961)and the Health of Older Adults-china,2008-2023

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

china CDC weekly 2024年第11期6卷 203-207,I0001-I0003页

作者： chi Shen Xi Chen School of Public Policy and Administration Xi’an Jiaotong UniversityXi’an CityShaanxi ProvinceChina Department of Health Policy and Management Yale School of Public HealthNew HavenCTU.S Department of Economics Yale UniversityNew HavenCTU.S

What is already known about this topic?There is mounting evidence indicating that the aging process initiates during early life stages,with in utero the individual’s environment playing a significant role.Consequently,it is crucial to comprehend the enduring effects of early life circumstances on health in old age.What is added by this report?In this study,we conducted a meta-analysis to examine the effects of the chinese Famine(1959–1961)on the health of older adults.We also explored potential mechanisms underlying these effects.What are the implications for public health practice?The complex interplay between early life circumstances,multiple health-related sectors,and healthy aging necessitates a comprehensive life-course approach and strategic interventions to enhance public health in an aging society.

关键词： life aging mount

Global collaboration of eye research--personal experience

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2024年第6期17卷 985-990页

作者： chi-Chao Chan Laboratory of Immunology National Eye InstituteNational Institutes of HealthBethesdaMD 20892-1858USA Zhongshan Ophthalmic Center Sun Yat-sen UniversityGuangzhou 5410060Guangdong ProvinceChina

On December 9,2023,I was privileged to be honored and participate in the Dr.chi Chao Chan Symposium on Global Collaboration of Eye Research as the Global Eye Genetic Consortium(GEGC)session,which was held in the 16th Congress of the Asia-Pacific Vitreo-Retina Society(APVRS)in Hong Kong.Along with my talk on“Global collaboration of eye research:personal experience”,other prominent international speakers provided their own perspectives on opportunities for networking,collaboration,and exchange of ideas with global leaders and experts in ophthalmic practice,research,and education.

关键词： speakers collaboration Global

Finite-time Prescribed Performance Time-Varying Formation Control for Second-Order Multi-Agent Systems With Non-Strict Feedback Based on a Neural Network Observer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1039-1050页

作者： chi Ma Dianbiao Dong the School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China

This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown nonlinearities.To eliminate nonlinearities,neural networks are applied to approximate the inherent dynamics of the system.In addition,due to the limitations of the actual working conditions,each follower agent can only obtain the locally measurable partial state information of the leader agent.To address this problem,a neural network state observer based on the leader state information is designed.Then,a finite-time prescribed performance adaptive output feedback control strategy is proposed by restricting the sliding mode surface to a prescribed region,which ensures that the closed-loop system has practical finite-time stability and that formation errors of the multi-agent systems converge to the prescribed performance bound in finite time.Finally,a numerical simulation is provided to demonstrate the practicality and effectiveness of the developed algorithm.

关键词： Finite-time control multi-agent systems neural network prescribed performance control time-varying formation control

维普期刊数据库

Beyond the lab:a nanoimprint metalens arraybased augmented reality

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2024年第5期13卷 801-802页

作者： chi Lio Haoran Ren School of Physics and Astronomy Monash UniversityMelbourneVICAustralia

A see-through augmented reality prototype has been developed based on an ultrathin nanoimprint metalens array,opening up a full-colour,video-rate,and low-cost 3D near-eye display.

关键词： cost ens imprint

Opinion Dynamics in Two-Layer Networks with Hypocrisy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of the Operations Research Society of china 2024年第1期12卷 109-132页

作者： chi Zhao Elena Parilina Saint Petersburg State University Saint Petersburg199034Russia Qingdao University School of Mathematics and StatisticsQingdao 266071ShandongChina

We propose a general concealed voter model(GCVM),in which individuals interact in two layers and can exchange their opinions in the internal layer.This interaction is not allowed in a CVM.By exchanging opinions in the internal layer,we mean that individuals share their real or internal opinions with their close friends.The process of opinion formation in GCVM is presented in the paper.We make the series of numerical simulations of GCVM with different network structures(both external and internal)and get some counterintuitive conclusions.For instance,we find out that sometimes with a relatively simple network structure of an external layer the consensus within the individuals’opinions cannot be reached,and if individuals in the network are not good at expressing their opinions publicly(in an external layer),exchanging opinions with their close friends(in an internal layer)is almost useless.

关键词： Opinion dynamics Voter model Concealed voter model General concealed voter model

Fixed-Time Cluster Optimization for Multi-Agent Systems Based on Piecewise Power-Law Design

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1301-1303页

作者： Suna Duan Xinchun Jia Xiaobo chi School of Mathematical Sciences Shanxi UniversityTaiyuan 030006China School of Automation and Software Engineering Shanxi UniversityTaiyuan 030013China

Dear Editor,This letter focuses on the fixed-time(FXT)cluster optimization problem of first-order multi-agent systems(FOMASs)in an undirected network,in which the optimization objective is the sum of the objective functions of all clusters.A novel piecewise power-law control protocol with cooperative-competition relations is proposed.Furthermore,a sufficient condition is obtained to ensure that the FOMASs achieve the cluster consensus within an FXT.

关键词： agent cluster optimization

维普期刊数据库博看期刊

在线全文

学校读者我要写书评

暂无评论

花瓣型胶囊机器人空间转弯磁矩研究

华中科技大学学报（自然科学版） 2018年第4期46卷 80-85页

作者：迟明路张永顺大连理工大学机械工程学院辽宁大连116024 大连理工大学精密与特种加工教育部重点实验室辽宁大连116024

为降低对肠道的扭曲作用,提出一种扭转力矩效应花瓣型胶囊机器人,实现了机器人与肠道隔离.对弯曲环境约束下的机器人运动学进行分析,建立万向旋转磁矢量空间磁力矩模型.为了实现胶囊机器人转弯时的流体扭转力矩在线检测,提出一种弯曲环... 详细信息

为降低对肠道的扭曲作用,提出一种扭转力矩效应花瓣型胶囊机器人,实现了机器人与肠道隔离.对弯曲环境约束下的机器人运动学进行分析,建立万向旋转磁矢量空间磁力矩模型.为了实现胶囊机器人转弯时的流体扭转力矩在线检测,提出一种弯曲环境内临界耦合转弯磁矩检测方法,以俯仰力矩为目标函数,通过主要目标法对转差角和水平夹角进行优化.研究结果表明：在一定水平夹角和转差角范围内,机器人俯仰力矩均减小,降低了机器人摆动,提高了转弯稳定性;该机器人显著减小了转弯时对肠道的扭曲作用,提高了非接触驱动性能和肠道内驱动安全性.

关键词：花瓣型胶囊机器人扭转力矩效应空间转差角转弯磁力矩稳定性

维普期刊数据库