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Optimal Design and Force Control of a Nine-Cable-Driven Parallel Mechanism for Lunar Takeoff Simulation

Chinese Journal of Mechanical Engineering 2019年第4期32卷 35-46页

作者： Wangmin Yi Yu zheng Weifang Wang XiaoqiangTang Xinjun Liu Fanwei Meng Department of Mechanical Engineering Tsinghua University Beijing 100084China Beijing Institute of Spacecraft EnvironMent Engineering China Academy of Space Technology Beijing 100094 China Beijing Engineering Research Center of the Intelligent AsseMbly Technology and EquipMent for Aerospace Product Beijing Institute of Spacecraft EnvironMent Engineering Beijing 100094China School of Mechanical Engineering and AutoMation Beihang University Beijing 100191China Beijing Institute of Radio MeasureMent Second Research Institute of the China Aerospace Science and Industry Group Beijing 100854 China

Traditional simulation methods are unable to meet the requirements of lunar takeo simulations, such as high force output precision, low cost, and repeated use. Considering that cable-driven parallel mechanisms have the advantages of high payload to weight ratio, potentially large workspace, and high-speed motion, these mechanisms have the potential to be used for lunar takeo simulations. Thus, this paper presents a parallel mechanism driven by nine cables. The purpose of this study is to optimize the dimensions of the cable-driven parallel mechanism to meet dynamic workspace requirements under cable tension constraints. The dynamic workspace requirements are derived from the kinematical function requests of the lunar takeo simulation equipment. Experimental design and response surface methods are adopted for building the surrogate mathematical model linking the optimal variables and the optimization indices. A set of dimensional parameters are determined by analyzing the surrogate mathematical model. The volume of the dynamic workspace increased by 46% after optimization. Besides, a force control method is proposed for calculating output vector and sinusoidal forces. A force control loop is introduced into the traditional position control loop to adjust the cable force precisely, while controlling the cable length. The e ectiveness of the proposed control method is verified through experiments. A 5% vector output accuracy and 12 hz undulation force output can be realized. This paper proposes a cable-driven parallel mechanism which can be used for lunar takeo simulation.

关键词： Force control Lunar takeo simulation Parallel robots Surrogate mathematical model

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Preparation of highly preferred orientation TiB_2 coatings

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Rare Metals 2006年第2期25卷 111-117页

作者： LI Jun LI Bing JIANG Lushan DONG zheng ＇e YE Yifu School of Materials Engineering Shanghai University of Engineering Science Shanghai 201620 China School of Resource and Environment Engineering East China University of Science and Technology Shanghai 200237 China School of Fashion Shanghai University of Engineering Science Shanghai 201620. China

This paper focuses on the preparation of titanium diboride （TiB2） coatings on the graphite substrate by continuous current plating （CCP） and pulse current plating （PIC） electrochemical techniques in fluoride electrolytes （LiF-NaF-KF） containing K2T1F6 and KBF4 as the electrochemically-active components at 700℃. Thick leveled and uniform coatings were obtained and were composed of relatively pure TiB2. The effect of the experimental parameters on the microstructure of the coatings was studied. The results showed the electrodeposition with PIC produced coatings with better quality, when compared with those obtained by CCP, under the conditions of the current density i = 0.6 A/cm^2, frequency = 100 hz, and todtofr = 4/1. XRD analysis indicated that the preferred orientation of coatings is （110） plane, which is in accordance with the prediction of the two-dimensional crystal nuclei theory. The effect of a ratio of ton/toff and frequency on the crystal size, textule coefficient and microstress was also investigated.

关键词： coatings titanium diboride electrodeposition molten salt

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Formation of the mass density peak at the magnetospheric equator triggered by EMIC waves

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Earth and Planetary Physics 2021年第1期5卷 32-41页

作者： ZuXiang Xue ZhiGang Yuan XiongDong Yu ShiYong huang zheng Qiao School of Electronic Information Wuhan UniversityWuhan 420072China

We report a simultaneous observation of two band electromagnetic ion cyclotron(EMIC)waves and toroidal Alfvén waves by the Van Allen Probe *** wave frequency analyses,the mass densityρis found to be locally peaked at the magnetic *** fluxes of ions(h the appearances of EMIC waves,indicating a heating of these ions by EMIC *** addition,the measured ion distributions also support the equatorial peak formation,which accords with the result of the frequency *** formation of local mass density peaks at the equator should be due to enhancements of equatorial ion concentrations,which are triggered by EMIC waves’perpendicular heating on low energy ions.

关键词： toroidal Alfvén waves EMIC waves magnetoseismology equatorial mass density peak

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Overoxidized poly(3,4-ethylenedioxythiophene)-gold nanoparticles-graphene-modified electrode for the simultaneous detection of dopamine and uric acid in the presence of ascorbic acid

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Journal of Pharmaceutical Analysis 2021年第6期11卷 699-708页

作者： Junqiang Pan Mei Liu Dandan Li haonan zheng Dongdong Zhang Department of Cardiovascular Medicine Xi'an Central HospitalXi'an710061China School of Pharmacy Xi'an Jiaotong University Health Science CenterXi'an710003China

An innovative,ternary nanocomposite composed of overoxidized poly(3,4-ethylenedioxythiophene)(OPEDOT),gold nanoparticles(Au NPs),and electrochemically reduced graphene oxide(ERGO)was prepared on a glassy carbon electrode(GCE)(OPEDOT-Au NPs-ERGO/GCE)through homogeneous chemical reactions and heterogeneous electrochemical *** morphology,composition,and structure of this nanocomposite were characterized by transmission electron microscopy,scanning electron microscopy,X-ray diffraction,and X-ray photoelectron *** electrochemical properties of the OPEDOT-Au NPs-ERGO/GCE were investigated by cyclic voltammetry using potassium ferricyanide and hexaammineruthenium(III)chloride redox probe *** modified electrode shows excellent electro-catalytic activity for dopamine(DA)and uric acid(UA)under physiological p h conditions,but inhibits the oxidation of ascorbic acid(AA).Linear voltammetric responses were obtained when DA concentrations of approximately 4.0-100μM and UA concentrations of approximately 20-100μM were *** detection limits(S/N=3)for DA and UA were 1.0 and 5.0μM,respectively,under physiological conditions and in the presence of 1.0 m M of *** developed method was applied to the simultaneous detection of DA and UA in human urine,where satisfactory recoveries from 96.7%to 105.0%were *** work demonstrates that the developed OPEDOT-Au NPs-ERGO ternary nanocomposite,with its excellent ion-selectivity and electro-catalytic activity,is a promising candidate for the simultaneous detection of DA and UA in the presence of AA in physiological and pathological studies.

关键词： Graphene Poly(3,4-ethylenedioxythiophene) Overoxidation Dopamine Uric acid Ascorbic acid

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Characteristics of the pressure profile in the accelerator on the RF negative ion source at ASIPP

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Nanotechnology and Precision Engineering 2023年第3期6卷 48-54页

作者： Mingshan Wu Luxiang Xu Yanbo Zhou Lizhen Liang Yelong zheng School of Fundamental Physics and Mathematical Sciences Key Laboratory of Gravitational Wave Precision Measurement of Zhejiang ProvinceTaiji Laboratory for Gravitational Wave UniverseHangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China University of Chinese Academy of Sciences Beijing 100049China Institute of Plasma Physics Chinese Academy of SciencesHefei 230031China State Key Laboratory of Precision Measuring Technology and Instruments Tianjin UniversityTianjin 300072China

Neutral beam injection(NBI)systems based on negative hydrogen ion sources-rather than the positive ion sources that have typically been used to date-will be used in the future magnetically confined nuclear fusion experiments to heat the *** collisions between the fast negative ions and neutral background gas result in a significant number of high-energy positive ions being produced in the acceleration area,and for the high-power long-pulse operation of NBI systems,this acceleration of positive ions back to the ion source creates heat load and material sputtering on the source *** difficulty cannot be ignored,with the neutral gas density in the acceleration region having a significant impact on the flux density of the backstreaming positive *** the work reported here,the pressure gradient in the acceleration region was estimated using an ionization gauge and a straightforward 1D computation,and it was found that once gas traveled through the acceleration region,the pressure dropped by nearly one order of magnitude,with the largest pressure drop occurring at the plasma *** computation also revealed that the pressure drop in the grid gaps was substantially smaller than that in the grid apertures.

关键词： Pressure gradient Negative ion source Aperture conductance Neutral beam injection

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Soundness Analysis of Compositional Model of Time-Based Petri Nets

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Wuhan University Journal of Natural Sciences 2011年第6期16卷 493-499页

作者： zheng hong JIANG Yue School of Imformation Science and Engineering EastChina University of Science and Technology Shanghai 200237China Training Center Jiangxi Electric Power CompanyNanchang 330077 Jiangxi China

Workflow management systems are widely used in improving the efficiency of business processes. To develop a workflow management system is the key to workflow modeling. In this paper, the compositional time net is presented to model workflow processes on the basis of the analyzing methods of time Petri nets and workflows, and to describe the static relationships and the dynamic semantics of the task of multiple workflow com- position. The paper puts more emphasis on checking the sotmdness of composed workflow, at the same time, combinational problems of non-conditional structure of the compositional time net are introduced and analyzed. A sufficient and necessary condition for determining the soundness of compositional nets is obtained.

关键词： verification soundness Time Petri nets

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Development of Integrated Braking and Steering System for Electric Bus

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仪器仪表学报 2013年第S1期34卷 138-141页

作者： Li Shuwei zheng Yaogang School of Automotive Engineering Yancheng Institute of Technology

Based on actual needs of lightweight,cost reduction,energy saving and convenient arrangement of electric bus,integrated braking and steering system is *** air compressor of braking system and the hydraulic pump of power steering system are drived by an electric *** key factors which will affect the performance of air compressor in the electric bus are analysed and air compressor of the braking system is *** active adaptive control and vibration isolation control technique are also applied to the electric *** and application show that the integrated braking and steering system can achieve the operation better in electric bus.

关键词： drive unit integrated system air compressor

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桁架式自升式风电安装船桩靴结构设计分析

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船舶标准化工程师 2025年第1期58卷 35-39+65页

作者：陈家旺郭勤静杨灵陈晓婷郑建建郑金川招商局重工(江苏)有限公司中南勘测设计研究院有限公司

为了设计、分析和优化一型大起重功能的桁架式自升式风电安装船的桩靴，确保桩靴按期备料、下料并开工建造，针对桩靴初始结构设计，采用中国船级社规范要求的2种加载方法，考虑预压载、偏心、正常操作以及风暴自存工况等，通过SESAM软... 详细信息

为了设计、分析和优化一型大起重功能的桁架式自升式风电安装船的桩靴，确保桩靴按期备料、下料并开工建造，针对桩靴初始结构设计，采用中国船级社规范要求的2种加载方法，考虑预压载、偏心、正常操作以及风暴自存工况等，通过SESAM软件进行初步结构强度分析。在此基础上对桩靴结构强度进行局部加强和设计优化，对整个桩靴内部板厚、舱壁板和开孔布置等进行二次优化设计，实现桩靴优化减重，降低材料成本，保证桩靴整体结构强度和运行安全，并形成一套完整的桩靴结构设计分析及优化方法。研究成果可为自升式风电安装船桩靴结构设计方案评估及系列化设计建造提供参考。

关键词：桁架式桩腿自升式风电安装船桩靴强度结构设计优化开孔布置优化

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Secrecy energy efficiency maximization for UAV-enabled multi-hop mobile relay system

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The Journal of China Universities of Posts and Telecommunications 2022年第3期29卷 81-91页

作者： Miao Jiansong Li hairui zheng Ziyuan Wang Chu Zhao Zhenmin Beijing Laboratory of Advanced Information Networks Beijing University of Posts and TelecommunicationsBeijing 100876China

To deal with the secrecy issues and energy efficiency issues in the unmanned aerial vehicles(UAVs) assisted communication systems, an UAV-enabled multi-hop mobile relay system is studied in an urban environment. Multiple rotary-wing UAVs with energy budget considerations are employed as relays to forward confidential information between two ground nodes in the presence of multiple passive eavesdroppers. The system secrecy energy efficiency(SEE), defined by the ratio of minimum achievable secrecy rate(SR) to total propulsion energy consumption(PEC), is maximized via jointly optimizing the trajectory and transmit power of each UAV relay. To solve the formulated non-convex fractional optimization problem subject to mobility, transmit power and information-causality constraints, an effective iterative algorithm is proposed by applying the updated-rate-assisted block coordinate decent method, successive convex approximation(SCA) technique and Dinkelbach method. Simulation results demonstrate the effectiveness of the proposed joint trajectory design and power control scheme.

关键词： secrecy transmission unmanned aerial vehicle(UAV) trajectory optimization mobile relay

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Research on Inter-turn Short-circuit Fault Diagnosis Method Based on high Frequency Voltage Residual for PMSM

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CES Transactions on Electrical Machines and Systems 2023年第3期7卷 256-265页

作者： Xiaobao Feng Bo Wang Chaohui Liu Jiayun Zeng zheng Wang School of Electrical Engineering Southeast UniversityNanjing 210096China IEEE National New Energy Vehicle Technology Innovation Center(NEVC) Beijing 100176China Nanjing Engineering Institute of Aircraft System Aviation Industry Corporation of ChinaNanjing 211106China

Inter-turn fault is a serious stator winding short-circuit fault of permanent magnet synchronous machine(PMSM). Once it occurs, it produces a huge short-circuit current that poses a great risk to the safe operation of PMSM. Thus, an inter-turn short-circuit fault(ITSCF) diagnosis method based on high frequency(hF) voltage residual is proposed in this paper with proper hF signal injection. First, the analytical models of PMSM after the ITSCF are deduced. Based on the model, the voltage residual at low frequency(LF) and hF can be obtained. It is revealed that the hF voltage residual has a stronger ITSCF detection capability compared to the LF voltage residual. To obtain optimal fault signature, a 3-phase symmetrical hF voltage is injected into the machine drive system, and the hF voltage residuals are extracted. The fault indicator is defined as the standard deviation of the 3-phase hF voltage residuals. The effectiveness of the proposed ITSCF diagnosis method is verified by experiments on a triple 3-phase PMSM. It is worth noting that no extra hardware equipment is required to implement the proposed method.

关键词： Inter-turn short-circuit fault(ITSCF) Permanent magnet synchronous machine(PMSM) high frequency(hF)injection Voltage residual Fault diagnosis

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