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Observer-Based Adaptive Robust Precision Motion Control of a Multi-Joint Hydraulic Manipulator

IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1213-1226页

作者： Zheng Chen Shizhao Zhou Chong Shen Litong Lyu junhui zhang Bin Yao State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027 Ocean College Zhejiang UniversityZhoushan 316021China School of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuang 050000 State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China School of Mechanical Engineering Purdue UniversityWest LafayetteIN 47907 USA

Hydraulic manipulators are usually applied in heavy-load and harsh operation tasks.However,when faced with a complex operation,the traditional proportional-integral-derivative(PID)control may not meet requirements for high control performance.Model-based full-state-feedback control is an effective alternative,but the states of a hydraulic manipulator are not always available and reliable in practical applications,particularly the joint angular velocity measurement.Considering that it is not suitable to obtain the velocity signal directly from differentiating of position measurement,the low-pass filtering is commonly used,but it will definitely restrict the closed-loop bandwidth of the whole system.To avoid this problem and realize better control performance,this paper proposes a novel observerbased adaptive robust controller(obARC)for a multi-joint hydraulic manipulator subjected to both parametric uncertainties and the lack of accurate velocity measurement.Specifically,a nonlinear adaptive observer is first designed to handle the lack of velocity measurement with the consideration of parametric uncertainties.Then,the adaptive robust control is developed to compensate for the dynamic uncertainties,and the close-loop system robust stability is theoretically proved under the observation and control errors.Finally,comparative experiments are carried out to show that the designed controller can achieve a performance improvement over the traditional methods,specifically yielding better control accuracy owing to the closed-loop bandwidth breakthrough,which is limited by low-pass filtering in fullstate-feedback control.

关键词： handle Observer filtering

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Mesenchymal stem cell-derived exosomes: Versatile nanomaterials for skin wound treatment

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Nano Research 2024年第4期17卷 2836-2856页

作者： Yuzhen Xiao Hexi Li junhui zhang Songyun Yang Chunsen zhang Yizhou Huang Xin Tang Huiqi Xie Department of Orthopedic Surgery and Orthopedic Research Institute Laboratory of Stem Cell and Tissue EngineeringState Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu 610041China West China School of Basic Medical Sciences and Forensic Medicine Sichuan UniversityChengdu 610041China West China School of Public Health and West China Fourth Hospital Sichuan UniversityChengdu 610041China Sports Medicine Center West China HospitalSichuan UniversityChengdu 610041China

Accumulating studies reveal that mesenchymal stem cells(MSCs)promote skin wound healing mainly through the paracrine effects.Exosomes,one of the crucial paracrine mediators in wound healing,are cell-derived nanosized membranous vesicles containing diverse bioactive cargoes.With the potent ability of modulating skin cell behaviors,MSC-derived exosomes(MSC-Exos)are regarded as a promising nanomaterial for regenerative wound therapy.Under hostile conditions,MSC-Exos are efficient in protecting skin cells from severe damage and restoring their function.According to recent studies,MSC-Exos possess remarkable pro-healing effects in a variety of skin wounds,typically resulting in increased wound closure,inhibited scar tissue formation,and better restoration of skin function.To further enhance the therapeutic potential of MSC-Exos,the development of applicable pretreatment strategies and the optimization of exosome delivery are under intensive investigation.Herein,we summarize current research progress of MSC-Exos for skin wound treatment,with an emphasis on the biological effects of these nanovesicles,the repair mechanisms,and future challenges in clinical translation.

关键词： exosomes mesenchymal stem cells diabetic wounds burn wounds scar wound healing

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Bionic lightweight design of limb leg units for hydraulic quadruped robots by additive manufacturing and topology optimization

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Bio-Design and Manufacturing 2024年第1期7卷 1-13页

作者： Huaizhi Zong junhui zhang Lei Jiang Kun zhang Jun Shen Zhenyu Lu Ke Wang Yanli Wang Bing Xu The State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China Unmanned Vehicle Research and Development Center China North Vehicle Research InstituteBeijing 100072China School of Mechatronic Engineering Nanchang UniversityNanchang 330031China Auclean High-Tech Ltd. Wuxi 214108China

Galloping cheetahs,climbing mountain goats,and load hauling horses all show desirable locomotion capability,which motivates the development of quadruped robots.Among various quadruped robots,hydraulically driven quadruped robots show great potential in unstructured environments due to their discrete landing positions and large payloads.As the most critical movement unit of a quadruped robot,the limb leg unit(LLU)directly affects movement speed and reliability,and requires a compact and lightweight design.Inspired by the dexterous skeleton–muscle systems of cheetahs and humans,this paper proposes a highly integrated bionic actuator system for a better dynamic performance of an LLU.We propose that a cylinder barrel with multiple element interfaces and internal smooth channels is realized using metal additive manufacturing,and hybrid lattice structures are introduced into the lightweight design of the piston rod.In addition,additive manufacturing and topology optimization are incorporated to reduce the redundant material of the structural parts of the LLU.The mechanical properties of the actuator system are verified by numerical simulation and experiments,and the power density of the actuators is far greater than that of cheetah muscle.The mass of the optimized LLU is reduced by 24.5%,and the optimized LLU shows better response time performance when given a step signal,and presents a good trajectory tracking ability with the increase in motion frequency.

关键词： Additive manufacturing Bionic lightweight design Limb leg unit Quadruped robot Trajectory tracking

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Deployment of Edge Computing Nodes in IoT:Effective Implementation of Simulated Annealing Method Based on User Location

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China Communications 2024年第1期21卷 279-296页

作者： junhui Zhao Ziyang zhang Zhenghao Yi Xiaoting Ma Qingmiao zhang School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China School of Information Engineering East China Jiaotong UniversityNanchang 330013China

Edge computing paradigm for 5G architecture has been considered as one of the most effective ways to realize low latency and highly reliable communication,which brings computing tasks and network resources to the edge of network.The deployment of edge computing nodes is a key factor affecting the service performance of edge computing systems.In this paper,we propose a method for deploying edge computing nodes based on user location.Through the combination of Simulation of Urban Mobility(SUMO)and Network Simulator-3(NS-3),a simulation platform is built to generate data of hotspot areas in Io T scenario.By effectively using the data generated by the communication between users in Io T scenario,the location area of the user terminal can be obtained.On this basis,the deployment problem is expressed as a mixed integer linear problem,which can be solved by Simulated Annealing(SA)method.The analysis of the results shows that,compared with the traditional method,the proposed method has faster convergence speed and better performance.

关键词： deployment problem edge computing internet of things machine learning

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Improved PSO-Extreme Learning Machine Algorithm for Indoor Localization

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China Communications 2024年第5期21卷 113-122页

作者： Qiu Wanqing zhang Qingmiao Zhao junhui Yang Lihua School of Information Engineering East China Jiaotong UniversityNanchang 330013China School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China

Wi Fi and fingerprinting localization method have been a hot topic in indoor positioning because of their universality and location-related features.The basic assumption of fingerprinting localization is that the received signal strength indication(RSSI)distance is accord with the location distance.Therefore,how to efficiently match the current RSSI of the user with the RSSI in the fingerprint database is the key to achieve high-accuracy localization.In this paper,a particle swarm optimization-extreme learning machine(PSO-ELM)algorithm is proposed on the basis of the original fingerprinting localization.Firstly,we collect the RSSI of the experimental area to construct the fingerprint database,and the ELM algorithm is applied to the online stages to determine the corresponding relation between the location of the terminal and the RSSI it receives.Secondly,PSO algorithm is used to improve the bias and weight of ELM neural network,and the global optimal results are obtained.Finally,extensive simulation results are presented.It is shown that the proposed algorithm can effectively reduce mean error of localization and improve positioning accuracy when compared with K-Nearest Neighbor(KNN),Kmeans and Back-propagation(BP)algorithms.

关键词： extreme learning machine fingerprinting localization indoor localization machine learning particle swarm optimization

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Single-cell transcriptomics reveals the ameliorative effect of rosmarinic acid on diabetic nephropathy-induced kidney injury by modulating oxidative stress and inflammation

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1661-1676页

作者： junhui Chen Qian zhang Jinan Guo Di Gu Jing Liu Piao Luo Yunmeng Bai Jiayun Chen Xinzhou zhang Sheng Nie Chunbo Chen Yulin Feng Jigang Wang National Pharmaceutical Engineering Center for Solid Preparation of Chinese Herbal Medicine Jiangxi University of Chinese MedicineNanchang 330006China Department of Pulmonary and Critical Care Medicine Shenzhen Institute of Respiratory Diseasesand Shenzhen Clinical Research Centre for GeriatricsShenzhen People's HospitalFirst Affiliated Hospital of Southern University of Science and TechnologySecond Clinical Medical College of Jinan UniversityShenzhen 518020China School of Traditional Chinese Medicine and School of Pharmaceutical Sciences Southern Medical UniversityGuangzhou 510515China Department of Urology and Shenzhen Clinical Research Centre for GeriatricsShenzhen People's Hospitalthe First Affiliated HospitalSouthern University of Science and TechnologyShenzhen 518020China Department of Urology the First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510230China Department of Nephrology Shenzhen Key Laboratory of Kidney Diseasesand Shenzhen Clinical Research Centre for GeriatricsShenzhen People's Hospitalthe First Affiliated HospitalSouthern University of Science and TechnologyShenzhen 518020China Department of Nephrology Nanfang Hospitalthe First Affiliated Hospital of Southern Medical UniversityGuangzhou 510515China Department of Critical Care Medicine Shenzhen People's Hospital(the Second Clinical Medical CollegeJinan Universitythe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen 518020China State Key Laboratory for Quality Esurance and Sustainable Use of Dao-di Herbs Artemisinin Research Centerand Institute of Chinese Materia MedicaChina Academy of Chinese Medical SciencesBeijing 100700China Department of Oncology the Affiliated Hospital of Southwest Medical UniversityLuzhou 646000China

Diabetic nephropathy(DN)is a severe complication of diabetes,characterized by changes in kidney structure and function.The natural product rosmarinic acid(RA)has demonstrated therapeutic effects,including anti-inflammation and anti-oxidative-stress,in renal damage or dysfunction.In this study,we characterized the heterogeneity of the cellular response in kidneys to DN-induced injury and RA treatment at single cell levels.Our results demonstrated that RA significantly alleviated renal tubular epithelial injury,particularly in the proximal tubular S1 segment and on glomerular epithelial cells known as podocytes,while attenuating the inflammatory response of macrophages,oxidative stress,and cytotox-icity of natural killer cells.These findings provide a comprehensive understanding of the mechanisms by which RA alleviates kidney damage,oxidative stress,and inflammation,offering valuable guidance for the clinical application of RA in the treatment of DN.

关键词： Rosmarinic acid Diabetic nephropathy scRNA sequencing Injury Oxidative stress Infiammation Proteomics

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Modeling of Large-Scale Hydrogen Storage System Considering Capacity Attenuation and Analysis of Its Efficiency Characteristics

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Energy Engineering 2024年第2期121卷 291-313页

作者： junhui Li Haotian zhang Cuiping Li Xingxu Zhu Ruitong Liu Fangwei Duan Yongming Peng Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology Ministry of Education(Northeast Electric Power University)Jilin132012China Ministry of Science and Technology Electric Power Research Institute of State Grid Liaoning Electric Power Co.Ltd.Shenyang110006China Northeast Electric Power Dispatching Control Center Northeast Branch of State Grid Corporation of ChinaShenyang110180China

In the existing power system with a large-scale hydrogen storage system,there are problems such as low efficiency of electric-hydrogen-electricity conversion and single modeling of the hydrogen storage system.In order to improve the hydrogen utilization rate of hydrogen storage system in the process of participating in the power grid operation,and speed up the process of electric-hydrogen-electricity conversion.This article provides a detailed introduction to the mathematical and electrical models of various components of the hydrogen storage unit,and also establishes a charging and discharging efficiency model that considers the temperature and internal gas partial pressure of the hydrogen storage unit.These models are of great significance for studying and optimizing gas storage technology.Through these models,the performance of gas storage units can be better understood and improved.These studies are very helpful for improving energy storage efficiency and sustainable development.The factors affecting the charge-discharge efficiency of hydrogen storage units are analyzed.By integrating the models of each unit and considering the capacity degradation of the hydrogen storage system,we can construct an efficiency model for a large hydrogen storage system and power conversion system.In addition,the simulation models of the hydrogen production system and hydrogen consumption system were established in MATLAB/Simulink.The accuracy and effectiveness of the simulation model were proved by comparing the output voltage variation curve of the simulation with the polarization curve of the typical hydrogen production system and hydrogen consumption system.The results show that the charge-discharge efficiency of the hydrogen storage unit increases with the increase of operating temperature,and H2 and O2 partial voltage have little influence on the charge-discharge efficiency.In the process of power conversion system converter rectification operation,its efficiency decreases with the increase of temperature,while in the proc

关键词： Hydrogen storage system simulation modeling electrolyzer fuel cell capacity loss

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Spherical cationic polymer networks with porphyrin photosensitizer for sustainable and efficient photocatalysis

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Nano Research 2024年第5期17卷 3934-3941页

作者： Lingling zhang Liwei Wu junhui Bao Longhui Li Zejun Liu Feng Bai Jie Ju Xi Yao Key Laboratory for Special Functional Materials of Ministry of Education School of Materials Science and EngineeringHenan UniversityKaifeng 475004China Department of Chemistry City University of Hong KongKowloonHong Kong 999077China

The continuous and sustainable photo-activity on micro-or nano-carriers has always been a key stepping stone in the industrialization of photo-catalysis,photo-synthesis,and photo-degradation.Herein,we report a new series of positively charged hollow microspheres carrying porphyrin moieties.Such hollow spheres are formed through crosslinking of well-ordered porous thin laminates,initiated by co-assembly of regular monomers and those decorated with porphyrin moieties.On the surface of an individual sphere,densely distributed positive sites attract anionic reactants.The superficial porphyrin decomposes the accumulated reactants under 1 Sun.After degradation and release of products,the photoactive sites are thereby renewed.We demonstrate that polymer network(1:10)exhibited superior sustainable photocatalytic performance with complete degradation of methyl orange(MO)in 40 min with no observable performance deterioration after six cycles.The established close loop of adsorption-reaction-release cycle makes possible many efficient and continuous photo-catalytic processes.

关键词： hydrogen bonding assembly porphyrin sustainable photo-activity anionic pollutant

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Rapid testing and prediction of soil–water characteristic curve of subgrade soils considering stress state and degree of compaction

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第12期15卷 3305-3315页

作者： junhui Peng Huiren Hu junhui zhang National Engineering Research Center of Highway Maintenance Technology Changsha University of Science and TechnologyChangsha410114China

The subgrade soil is generally in saturated or unsaturated condition. To analyze complex thermo-hydro-mechanical-chemical (THMC) behaviors of subgrade, it is essential to determine the soil–water characteristic curve (SWCC) that represents the relationship between matric suction and moisture content. In this study, a full-automatic rapid stress-dependent SWCC pressure-plate extractor was developed. Then, the influences of overburden stress and degree of compaction on the SWCC of subgrade soil such as high liquid limit silt (MH) and low liquid limit clay (CL) were analyzed. Accordingly, a new model taking into account the influences of overburden stress and degree of compaction based on the well-known Van Genuchten (VG) SWCC fitting model was presented and validated. The results show that with the increase of the degree of compaction and overburden stress, the saturated moisture content of subgrade soil decreases, while the air-entry value increases and the transition section curve becomes flat. The influences of the degree of compaction and overburden stress on the SWCC of MH is greater than that of CL. Meanwhile, there was a satisfactory agreement between the prediction and measurement, indicating a good performance of the new model for predicting the SWCC.

关键词： Subgrade soil Soil–water characteristic curve(SWCC) Overburden stress Degree of compaction Prediction mode

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Influence of Piston Number on Churning Losses in Axial Piston Pumps

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Chinese Journal of Mechanical Engineering 2022年第5期35卷 194-207页

作者： Ying Li Xing Chen Hao Luo junhui zhang Jin zhang School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China State Key Laboratory of Fluid Power Transmission and Control Zhejiang UniversityHangzhou 310027China

Raising the rotational speed of an axial piston pump is useful for improving its power density;however,the churning losses of the piston increase significantly with increasing speed,and this reduces the performance and efficiency of the axial piston pump.Currently,there has been some research on the churning losses of pistons;however,it has rarely been analyzed from the perspective of the piston number.To improve the performance and efficiency of the axial piston pump,a computational fluid dynamics(CFD)simulation model of the churning loss was established,and the effect of piston number on the churning loss was studied in detail.The simulation analysis results revealed that the churning losses initially increased as the number of pistons increased;however,when the number of pistons increased from six to nine,the torque of the churning losses decreased because of the hydrodynamic shadowing effect.In addition,in the analysis of cavitation results,it was determined that the cavitation area of the axial piston pump was mainly concentrated around the piston,and the cavitation became increasingly severe as the speed increased.By comparing the simulation results with and without the cavitation model,it was observed that the cavitation phenomenon is beneficial for the reduction of churning losses.In this study,a piston churning loss test rig that can eliminate other friction losses was established to verify the accuracy of the simulation results.A comparative analysis indicated that the simulation results were consistent with the actual situation.In addition,this study also conducted a simulation study on seven and nine piston pumps with the same displacement.The simulation results revealed that churning losses of the seven pistons were generally greater than those of the nine pistons under the same displacement.In addition,regarding the same piston number and displacement,reducing the pitch circle radius of piston bores is effective in reducing the churning loss.This research analyzes the effect of piston number on the

关键词： Axial piston pumps Churning losses Pistons CFD simulations Experimental study

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