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Dynamic modeling and RBF neural network compensation control for space flexible manipulator with an underactuated hand

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Chinese Journal of Aeronautics 2024年第3期37卷 417-439页

作者： Dongyang SHANG Xiaopeng LI meng yin Fanjie LI School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China

In space operation,flexible manipulators and gripper mechanisms have been widely used because of light weight and ***,the vibration caused by slender structures in manipulators and the parameter perturbation caused by the uncertainty derived from grasping mass variation cannot be *** existence of vibration and parameter perturbation makes the rotation control of flexible manipulators difficult,which seriously affects the operation accuracy of ***’s more,the complex dynamic coupling brings great challenges to the dynamics modeling and vibration *** solve this problem,this paper takes the space flexible manipulator with an underactuated hand(SFMUH)as the research *** dynamics model considering flexibility,multiple nonlinear elements and disturbance torque is established by the assumed modal method(AMM)and Hamilton’s principle.A dynamic modeling simplification method is proposed by analyzing the nonlinear ***’s more,a sliding mode control(SMC)method combined with the radial basis function(RBF)neural network compensation is ***,the control law is designed using a saturation function in the control method to weaken the chatter *** the help of neural networks to identify the uncertainty composition in the SFMUH,the tracking accuracy is *** results of ground control experiments verify the advantages of the control method for vibration suppression of the SFMUH.

关键词： Space flexible manipulator RBF neural network Underactuated hand Dynamic models Model simplification

Nitrogen doping and graphitization tuning coupled hard carbon for superior potassium-ion storage

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Journal of Energy Chemistry 2020年第10期29卷 327-334页

作者： Junxian Hu Yangyang Xie meng yin Zhian Zhang School of Metallurgy and Environment Central South UniversityChangsha 410083HunanChina

Hard carbon material is one of the most promising anode materials for potassium ion batteries(PIBs)due to its distinct disordered and non-expandable ***,the intrinsically disordered microarchitecture of hard carbon results in low electric conductivity and poor rate ***,nitrogendoped and partially graphitized hard carbons(NGHCs)derived from commercial coordination compound precursor-ethylenediaminetetraacetic acid(EDTA)disodium cobalt salt hydrate are designed and prepared as high-performance PIBs anode *** means of a facile annealing method,nitrogen elements and graphitic domains can be controllably introduced to *** resulting NGHCs show structural merits of mesoporous construction,nitrogen doping and homogeneous graphitic domains,which ensures fast kinetics and electron *** in anode for PIBs,NGHCs exhibit robust rate capability with high reversible capacity of 298.8 m Ah g^-1 at 50 m A g^-1,and stable cycle stability of 137.6 mAh g^-1 at 500 m A g^-1 after 1000 ***,the ex situ Raman spectra reveal a mixture"adsorption-intercalation mechanism"for potassium storage of *** importantly,full PIBs by pairing with perylenetetracarboxylic dianhydride(PTCDA)cathode demonstrate the promising potential of practical *** terms of commercial precursor,facile synthesis and long cycle lifespan,NGHCs represent a brilliant prospect for practical large-scale applications.

关键词： Hard carbon Nitrogen doping Graphitic domains Potassium ion batteries Adsorption-intercalation mechanism

The Smallest Degree Sum That Yields Potentially Kr＋1 - K3-Graphic Sequences

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Acta Mathematicae Applicatae Sinica 2006年第3期22卷 451-456页

作者： meng-xiao yin School of Computer and Electronics Information Guangxi University Nanning 530004 China Department of Applied Mathematics Hainan University Haikou 570228 China

Let a（Kr,＋1 - K3,n） be the smallest even integer such that each n-term graphic sequence п= （d1,d2,…dn） with term sum σ（п） = d1 ＋ d2 ＋…＋ dn 〉 σ（Kr＋1 -K3,n） has a realization containing Kr＋1 - K3 as a subgraph, where Kr＋1 -K3 is a graph obtained from a complete graph Kr＋1 by deleting three edges which form a triangle. In this paper, we determine the value σ（Kr＋1 - K3,n） for r ≥ 3 and n ≥ 3r＋ 5.

关键词： Graph degree sequence potentially Kr+1-K3-graphic sequence

Dynamic Performance Investigation of A Spar-Type Floating Wind Turbine Under Different Sea Conditions

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China Ocean Engineering 2018年第3期32卷 256-265页

作者： WANG Han HU Zhi-qiang meng Xiang-yin State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai 200240China School of Engineering Newcastle UniversityNewcastle upon TyneNE1 7RU UK

Both numerical calculation and model test are important techniques to study and forecast the dynamic responses of the floating offshore wind turbine(FOWT). However, both the methods have their own limitations at present. In this study, the dynamic responses of a 5 MW OC3 spar-type floating wind turbine designed for a water depth of 200 m are numerically investigated and validated by a 1:50 scaled model test. Moreover, the discrepancies between the numerical calculations and model tests are obtained and discussed. According to the discussions, it is found that the surge and pitch are coupled with the mooring tensions, but the heave is independent of them. Surge and pitch are mainly induced by wave under wind wave conditions. Wind and current will induce the low-frequency average responses, while wave will induce the fluctuation ranges of the responses. In addition, wave will induce the wavefrequency responses but wind and current will restrain the ranges of the responses.

关键词： spar-type floating wind turbine dynamic response numerical calculation model test time domain analysis frequency domain analysis

Filtered-beam-search-based approach for operating theatre scheduling

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High Technology Letters 2015年第1期21卷 1-7页

作者：周炳海 yin meng School of Mechanical Engineering Tongji University

To improve the efficiency of operating rooms, reduce the hospital＇ s costs and improve the level of service qualities, a scheduling method is presented based on a filtered-beam-search-based algo- rithm. Firstly, a scheduling problem domain is described. Mathematical programming models are al- so set up with an objective function of minimizing related costs of the system. On the basis of the de= scriptions mentioned above, a solving policy of generating feasible scheduling solutions is estab- lished. Combining with the speeific constraints of operation theatres, a filtered-beam-search-based algorithm is put forward to solve scheduling problems. Finally, simulation experiments are designed. The performance of the proposed algorithm is evaluated and compared with that of other approaches through simulations. Results indicate that the proposed algorithm can reduce costs, and are of prac- ticality and effectiveness.

关键词： operating theatres scheduling algorithm filtered beam search costs

Rotation Angle Control Strategy for Telescopic Flexible Manipulator Based on a Combination of Fuzzy Adjustment and RBF Neural Network

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Chinese Journal of Mechanical Engineering 2022年第4期35卷 203-226页

作者： Dongyang Shang Xiaopeng Li meng yin Fanjie Li Bangchun Wen School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhen 518055China

The length of fexible manipulators with a telescopic arm alters during *** dynamic parameters of telescopic fexible manipulators exhibit signifcant time-varying characteristics owing to variations in *** an increase in the manipulators’length,the nonlinear terms caused by fexibility in the manipulators’dynamic equations cannot be *** time-varying characteristics and nonlinear terms of telescopic fexible manipulators cause fuctuations in rotation angles,which afect the operation accuracy of *** this study,a control strategy based on a combination of fuzzy adjustment and an RBF neural network is utilized to improve the control accuracy of fexible telescopic ***,the dynamic equation of the manipulators is established using the assumed mode method and Lagrange’s principle,and the infuence of nonlinear terms is ***,a combined control strategy is proposed to suppress the fuctuation of the rotation angle in telescopic fexible *** variation ranges of the feedforward PD controller parameters are determined by the pole placement strategy and length of the *** rules are utilized to adjust the controller parameters in *** RBF neural network is utilized to identify and compensate the uncertain part of the dynamic model of the fexible *** uncertain part comprises time-varying parameters and nonlinear ***,numerical simulations and prototype experiments prove the efectiveness of the combined control *** results prove that the proposed control strategy has a smaller standard deviation of ***,the combined control strategy is more suitable for telescopic fexible manipulators,which can efectively improve the control accuracy of rotation angles.

关键词： Flexible manipulator RBF neural network Fuzzy control Dynamic uncertainty

A functional PVA aerogel-based membrane obtaining sutureability through modified electrospinning technology and achieving promising anti-adhesion effect after cardiac surgery

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Bioactive Materials 2022年第4期7卷 355-366页

作者： Dawei Jin Shuofei Yang Shuting Wu meng yin Haizhu Kuang Department of Cardiothoracic Surgery Shanghai Children’s Medical CenterSchool of MedicineShanghai Jiao Tong University1678 Dong Fang RoadShanghai200127People’s Republic of China Department of Vascular Surgery Renji HospitalSchool of MedicineShanghai Jiao Tong University160 Pujian RoadShanghai200127People’s Republic of China Department of Pharmacy The Third Affiliated Hospital(The Affiliated Luohu Hospital)of Shenzhen UniversityShenzhen518001Guangdong ProvincePeople’s Republic of China

Pericardial barrier destruction,inflammatory cell infiltration,and fibrous tissue hyperplasia,trigger adhesions after cardiac *** are few anti-adhesion materials that are both functional and sutureable for pericardial ***,a few studies have reported on the mechanism of preventing pericardial ***,a functional barrier membrane with sutureability was developed via a modified electrospinning *** was composed of poly(L-lactide-co-caprolactone)(PLCL)nanofibers,poly(vinyl alcohol)(PVA)aerogel,and melatonin,named *** PPMT had a special microstructure manifested as a staggered arrangement of nanofibers on the surface and a layered macroporous aerogel structure in a *** providing the porosity and hydrophilicity obtained from PVA,the structure also had suitable mechanical properties for stitching due to the addition of PLCL ***,it inhibited the proliferation of fibroblasts by suppressing the activation of Fas and P53,and achieved anti-inflammatory effects by affecting the activity of inflammatory cells and reducing the release of pro-inflammatory factors,such as interleukin 8(IL-8)and tumor necrosis factorα(TNF-α).Finally,in vivo transplantation showed that it up-regulated the expression of matrix metalloproteinase-1(MMP1)and tissue inhibitor of metalloproteinase-1(TIMP1),and down-regulated the expression of Vinculin and transforming growth factorβ(TGF-β)in the myocardium,thereby reducing the formation of ***,these results demonstrate a great potential of PPMT membrane for practical application to anti-adhesion.

关键词： Anti-Adhesion PVA aerogel-Based membrane Sutureability Modified electrospinning technology Pericardial reconstruction

Ethylene/1-Hexene Copolymerization with Modified Ziegler-Natta Catalyst

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Chemical Research in Chinese Universities 2019年第6期35卷 1089-1094页

作者： yin meng ZHANG Zhiqiang XIONG Yujie LIU Min ZHANG Yan MI Puke Key Laboratory for Ultrafine Materials Ministry of EducationShanghai Key Laboratory of Advanced Polymeric MaterialsSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237P.R.China

Siloxane compounds were treated with the compounds containing internal donors,such as aromatic ester,phosphate,or 1,3-diether compounds,and the resulting intermediates were further reacted with TiCl4 to form the modified Ziegler-Natta catalysts for ethylene/1-hexene(E-H)*** the modified Ziegler-Natta catalysts,the effect of the internal donors and the molar ratio of alcohol to magnesium on the catalyst performance was investigated by the orthogonal *** synthetic method of the catalysts was also optimized by choosing the proper way to mix the internal *** branch degree,sequence structure,molecular weight,and molecular weight distribution of the copolymer products were determined by Fourier transform infrared spectroscopy(FTIR),carbon-13 nuclear magnetic resonance(^13C NMR)spectrometry and gel permeation chromatography(GPC).Under the optimum conditions,the catalytic system with tetraethyl orthosilicate and 2,2-dimethoxypropane as the internal donors exhibited the best performance with an activity of 926.74 g copolymer/(g Cat·h^?1).The branch degree,1-hexene content,and molecular weight distribution of the resulting copolymers reached up to 40 branches/1000C,5.99%and 5.8,respectively.

关键词： Ziegler-Natta catalyst Internal donor Lewis base Ethylene-olefin copolymerization Copolymer structure

Recent Progress in Networked Control Systems——A Survey

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International Journal of Automation and computing 2015年第4期12卷 343-367页

作者： Yuan-Qing Xia Yu-Long Gao Li-Ping Yan meng-yin Fu School of Automation Beijing Institute of Technology

For the past decades,networked control systems(NCSs),as an interdisciplinary subject,have been one of the main research highlights and many fruitful results from different aspects have been *** these growing research trends,it is significant to consolidate the latest knowledge and information to keep up with the research *** this paper,the results of different aspects of NCSs,such as quantization,estimation,fault detection and networked predictive control,are *** addition,with the development of cloud technique,cloud control systems are proposed for the further development of NCSs.

关键词： Networked control systems quantization filter data fusion fault detection networked predictive control cloud control systems.