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基于类V型柔性铰链的微位移放大机构

Stabilization/solidification mechanisms of tin tailings and fuming slag-based geopolymers for different heavy metals

光学精密工程 2017年第4期25卷 999-1008页

作者：刘敏张宪民华南理工大学广东省精密装备与制造技术重点实验室广东广州510641

采用新型高精度类V型柔性铰链设计了柔性微位移放大机构,以减小该类机构的寄生运动并提高其动力学性能.对类V型柔性铰链与最常见的高精度直圆型柔性铰链的性能进行了比较;在考虑柔性铰链转动中心偏移量的基础上,基于弹性力学和材料力学... 详细信息

采用新型高精度类V型柔性铰链设计了柔性微位移放大机构,以减小该类机构的寄生运动并提高其动力学性能.对类V型柔性铰链与最常见的高精度直圆型柔性铰链的性能进行了比较;在考虑柔性铰链转动中心偏移量的基础上,基于弹性力学和材料力学理论推导了基于类V型柔性铰链和基于直圆型柔性铰链的两类二级杠杆式微位移放大机构的放大比.采用ANSYS软件,建立了放大机构的有限元模型,验证了位移放大比的理论推导,并对上述两类放大机构的位移放大比、寄生运动和固有频率进行了仿真和比较.有限元分析结果显示:基于类V型柔性铰链的放大机构有着更小的寄生运动和更高的固有频率,且前2阶固有频率分别是基于直圆型柔性铰链放大机构的1.68倍和1.41倍.最后,采用微视觉测量系统测量了两类放大机构的位移放大比和寄生运动.结果表明:基于类V型和直圆型柔性铰链放大机构的放大比和相对寄生运动比分别为4.387、4.529和0.314 7、0.334 2,显示类V型柔性铰链用于微位移放大机构可有效减小寄生运动并提高动力学性能.

关键词：位移放大机构类V型柔性铰链直圆型柔性铰链寄生运动固有频率

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 43-55页

作者： xian Zhou Zhengfu zhang Hui Yang School of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093China Kunming Metallurgical Research Institute Co. Ltd.Kunming650031China

Tin mine tailings(TMT)and fuming slag(FS)contain many heavy metals(As,Cr,Cu,Zn and Mn)that cause severe pollution to the ***,geopolymers were prepared using TMT,FS and flue gas desulfurization gypsum(FGDG)to immobilize heavy metals,and their compressive strength and heavy metal leaching toxicity were *** was first determined that T4F5(TMT:FS=4:5)sample exhibited the highest compressive strength(7.83 MPa).T4F5 achieved 95%immobilization efficiency for As and Cr,and nearly 100%for Cu,Zn and Mn,showing good immobilization performance.A series of characterization analyses showed that heavy metal cations can balance the charge in the geopolymer and replace Al in the geopolymer structure to form covalent *** addition,about 2%–20%of heavy metal Fe was immobilized in hydration products,heavy metal hydroxides and non-bridging Si–O and Al–O coordination with silica-aluminate ***_(3)^(3−) was oxidized into AsO_(4)^(3−),which may form Ca–As or Fe–As ***_(2)O_(7)^(2−)was converted to CrO_(4)^(2−)under alkaline environment and then combined with OH−to form Cr(OH)3 ***^(2+)may react directly with dissolved silicate to form Mn_(2)SiO_(4) and also form Mn(OH)_(2) *** unstable Mn(OH)_(2) can be further oxidized to MnO_(2).The heavy metal cations were immobilized in the silicoaluminate lattice,while the anions tended to form insoluble *** results may benefit the industry and government for better handling of TMT,FS and solid wastes containing the abovementioned five heavy metals.

关键词： Heavy metals Cementitious materials Tin tailings Stabilization/solidification Redox

Three-dimensional porous bimetallic metal–organic framework/gelatin aerogels: A readily recyclable peroxymonosulfate activator for efficient and continuous organic dye removal

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Chinese Journal of Chemical Engineering 2024年第7期71卷 193-202页

作者： Wenlong xiang xian zhang Rou Xiao Yanhui zhang College of Chemistry Chemical Engineering and EnvironmentFujian Province Key Laboratory of Morden Analytical Science and Separation TechnologyMinnan Normal UniversityZhangzhou 363000China Fujian Provincial University Key Laboratory of Pollution Monitoring and Control Minnan Normal UniversityZhangzhou 363000China

As promising catalysts for the degradation of organic pollutants,metal–organic frameworks(MOFs)often face limitations due to the particle agglomeration and challenging recovery in liquid-catalysis application,stemming from their powdery *** macroscopic structures from pulverous MOF is thus of great importance for broadening their practical *** this study,three-dimensional porous MOF aerogel catalysts were successfully fabricated for degrading organic dyes by activating peroxymonosulfate(PMS).MOF/gelatin aerogel(MOF/GA)catalysts were prepared by directly integrating bimetallic FeCo-BDC with gelatin solutions,followed by freeze-drying and low-temperature *** FeCo-BDC-0.15/GA/PMS system exhibited remarkable performance in degrading various organic dyes,eliminating 99.2%of rhodamine B within a mere 5 *** to the GA/PMS system,there was over a 300-fold increase in the reaction rate ***,high removal efficiency was maintained across varying conditions,including different solution pH,co-existing inorganic anions,and natural water *** trapping experiments and electron paramagnetic resonance analysis revealed that the degradation involved radical(SO_(4)^(-)·)and non-radical routes(^(1)O_(2)),of which ^(1)O_(2) was ***,even after a continuous 400-min reaction in a fixed-bed reactor at a liquid hourly space velocity of 27 h^(-1),the FeCo-BDC/GA composite sustained a degradation efficiency exceeding 98.7%.This work presents highly active MOF-gelatin aerogels for dye degradation and expands the potential for their large-scale,continuous treatment application in organic dye wastewater management.

关键词： Catalyst Environment Wastewater Metal–organic framework Gelatin aerogel Peroxymonosulfate

Limit Theorems for Critical Galton-Watson Processes with Immigration Stopped at Zero

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Acta Mathematica Sinica,English Series 2024年第2期40卷 435-450页

作者： Dou Dou LI Mei zhang xian Yu zhang College of Statistics and Data Science Faculty of ScienceBeijing University of TechnologyBeijing 100124P.R.China Laboratory of Mathematics and Complex Systems(ministry of Education) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875P.R.China

In this paper,we consider a critical Galton-Watson branching process with immigration stopped at zero *** precise estimation on the probability generating function of the n-th population are obtained,and the tail prob... 详细信息

关键词： Branching immigration critical life period limit theorems

Hybrid vibration isolation optimization of a flexible manipulator based on neural network agent model

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Chinese Journal of Aeronautics 2024年第5期37卷 482-505页

作者： Yongxin zhang Liang LI Dingguo zhang Wei-Hsin LIAO xian GUO School of Science Nanjing University of Science and TechnologyNanjing 210094China Department of Mechanical and Automation Engineering The Chinese University of Hong KongHong KongChina

Segmented Active Constrained Layer Damping(SACLD)is an intelligent vibration-damping structure,which could be applied to the sectors of aviation,aerospace,and transportation engineering to reduce the vibration of flexible ***,machine learning technology is widely used in the engineering field because of its efficient multi-objective *** dynamic simulation of a rotational segmental flexible manipulator system is presented,in which enhanced active constrained layer damping is carried out,and the neural network model of Genetic Algorithm-Back Propagation(GA-BP)algorithm is *** suppression and structural optimization of the SACLD manipulator model are studied based on vibration mode and damping *** modal responses of the SACLD manipulator model at rest and rotation are *** addition,the four model indices are optimized using the GA-BP neural network:axial incision size,axial incision position,circumferential incision size,and circumferential incision ***,the best model for vibration suppression is obtained.

关键词： Machine learning Vibration suppression Flexible manipulator Segmented active constrained layer damping Structural optimization

Hybrid electromechanical properties of hetero-doped and homogeneously bonded dual-mode pressure sensor for indoor body area network node

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Science China(Information Sciences) 2024年第1期67卷 240-253页

作者： Junbin YU Shuai xian Jinbiao MU min WANG Yin WANG Xiaojuan HOU Le zhang Jian HE Jiliang MU Xiujian CHOU Science and Technology on Electronic Test and Measurement Laboratory North University of China Sichuan Aerospace Fenghuo Servo Control Technology Corporation

Pressure sensors are considerably important for continuous monitoring of human movement and the surrounding environment to construct a caregiving system for the elderly living *** challenge for pressure sensors that still remains is combining self-driven,comfort,and ***,an all-in-one conformal pressure sensor(ACPS) based on a homogeneous integrated triboelectric-piezoelectric hybrid sensor is *** ACPS has dual-mode sensing properties due to coupling triboelectrification and piezoelectric effect ensuring a stable response to various external ***-coated glass microspheres and polyacrylonitrile were uniformly filleted into the silicone rubber substrate using a hetero-doping method to create a stretchable electrode layer with flexible conformal characteristics and a piezoelectric layer with excellent piezoelectric properties,***,the triboelectric layer was fabricated using the same silicone rubber,allowing ACPS to be homogeneously bonded into an all-in-one structure with reliable *** allowed various functional layers to have outstanding interface characteristics and thus improve the electrical transmission *** developed ACPS had outstanding sensitivity(1.04 V/104Pa),high linearity(about 0.984),a wide measurement range(10–700 k Pa),and can accurately and continuously distinguish multiple ***,using a homemade signal processing circuit,ACPSs can be deployed in the human body and the room as indoor body area network *** successfully applied to the remote tracking of daily dynamic home life and the remote operation of small electrical equipment,these ACPSs can achieve real-time caregiving for the elderly living *** an application area desperately needed by society,this study envisions a caregiving system for the elderly living alone without violating personal privacy.

关键词： dual-mode pressure sensor homogeneous bonding all-in-one structure indoor body area network node elderly caregiving microsystem

Accumulated-state-error-based event-triggered sampling scheme and its application to H∞ control of sampled-data systems

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Science China(Information Sciences) 2024年第6期67卷 328-341页

作者： xian-ming zhang Qing-Long HAN Bao-Lin zhang Xiaohua GE Dawei zhang School of Science Computingand Engineering TechnologiesSwinburne University of Technology College of Automation and Electronic Engineering Qingdao University of Science & Technology School of Mathematics Shandong University

This paper is concerned with event-triggered H∞control of sampled-data systems. Its novelties lie in three aspects:（i） A novel accumulated-state-error-based event-triggered scheme is introduced by comparing the integral of the state error from tk to t with the system state sampled at tk. This condition works well due to the fact that the so-called Zeno behaviour does not occur.（ii） A novel Lyapunov functional is constructed to establish a criterion to ensure some certain H∞performance of the closed-loop system. This Lyapunov functional is dependent on the integral of the state error involved in the event-triggered scheme.（iii） Under the event-triggered sampling scheme, suitable state-feedback controllers can be designed rather than be given a priori. Moreover, a self-triggered implementation of the proposed event-triggered sampling scheme is presented as well. Finally, a batch reactor model and an inverted pendulum system are given to demonstrate the effectiveness of the proposed method.

关键词： event-triggered sampling self-triggered implementation H ∞ control looped-functional

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随机荷载作用下刚性路面动态响应研究

振动与冲击 2015年第19期34卷 126-130,137页

作者：张献民胡鹏中国民航大学机场学院天津300300

为了研究车辆随机荷载作用下刚性路面的动态响应,基于ANSYS软件,应用1/4车辆模型,得出其在路面不平度激励下的随机荷载,简化了荷载的求解,建立了路面三维有限元模型,讨论了在随机荷载作用下结构层参数对路面动位移幅值及面层层底拉应力... 详细信息

为了研究车辆随机荷载作用下刚性路面的动态响应,基于ANSYS软件,应用1/4车辆模型,得出其在路面不平度激励下的随机荷载,简化了荷载的求解,建立了路面三维有限元模型,讨论了在随机荷载作用下结构层参数对路面动位移幅值及面层层底拉应力幅值的影响规律。结果表明,面层厚度和土基模量对路面动位移幅值影响最大,当面层厚度超过30 cm、土基模量超过60 MPa时,继续增大以上结构层参数路面动位移幅值不再有明显减少;当土基模量小于60MPa继续减少时,要实现路面动位移幅值的不变,需要增加的面层厚度幅度逐渐变大;面层模量及厚度对面层层底拉应力幅值影响最大。

关键词：道路工程刚性路面三维有限元结构层参数随机荷载动位移幅值层底拉应力幅值

考虑减速机背隙的3-RRR并联机构的运动学标定

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华南理工大学学报（自然科学版） 2016年第7期44卷 47-54页

作者：张宪民曾磊华南理工大学广东省精密装备与制造技术重点实验室广东广州510640

为了提高宏动并联平台的定位精度,推导了考虑减速机背隙的3-RRR并联机构误差模型,同时建立不考虑减速机背隙的误差模型用于对比,以验证该模型的有效性;通过实验测量末端平台位姿误差并分别辨识两个误差模型参数,根据距离反比法进行空间... 详细信息

为了提高宏动并联平台的定位精度,推导了考虑减速机背隙的3-RRR并联机构误差模型,同时建立不考虑减速机背隙的误差模型用于对比,以验证该模型的有效性;通过实验测量末端平台位姿误差并分别辨识两个误差模型参数,根据距离反比法进行空间插值实现误差补偿并完成运动学标定.根据标定结果修正逆运动学模型,通过测量末端平台位姿误差分布可知,文中提出的考虑减速机背隙的误差模型优于不考虑减速机背隙的误差模型.文中提出的考虑减速机背隙的运动学标定提高了并联机构的定位精度,为该类并联机构用于高精密宏微结合提供了基础.

关键词：并联平台减速机背隙运动学标定距离反比法位姿误差定位精度