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A New Recursive Composite Adaptive Controller for Robot Manipulators

Space(Science & Technology) 2021年第1期2021卷 77-83页

作者： Jianfei Li Yaobing Wang Zhiyong Liu Xin Jing Chengwei Hu The State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190China Beijing Key Laboratory of Intelligent Space Robotic System Technology and Applications Beijing Institute of Spacecraft System EngineeringBeijing 100094China State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China

In this paper,a new recursive implementation of composite adaptive control for robot manipulators is *** investigate the recursive composite adaptive algorithm and prove the stability directly based on the Newton-Euler equations in matrix form,which,to our knowledge,is the first result on this point in the *** proposed algorithm has an amount of computation O(n),which is less than any existing similar algorithms and can satisfy the computation need of the complicated multidegree *** manipulator of the Chinese Space Station is employed as a simulation example,and the results verify the effectiveness of this proposed recursive algorithm.

关键词： Robot manipulators robot

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Experimental evaluation of a 10-kW parabolic trough solar reactor prototype driving Ni-based chemical looping redox cycle with methane for solar fuel production

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Science China(Technological Sciences) 2024年第12期67卷 3741-3754页

作者： JIANG QiongQiong CAO YaLi SUN Fan XING XueLi HONG Hui Key Laboratory of Power Station Energy Transfer Conversion and System of MOE School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China State Power Investment Corporation Hydrogen Energy Beijing 100033China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100049China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China China Huaneng Group Clean Energy Association Research Institute Beijing 102209China

Solar fuels can be cost-effectively produced using solar-driven thermochemical *** thermochemical processes can not only effectively utilize solar energy but also achieve clean conversion of fossil *** this method,the solar energy level can be upgraded,and the irradiation fluctuation can be *** is worth noting that solar reactors play an important role in this *** this study,we demonstrated a 10-kW parabolic trough solar-driven reactor prototype for methane reforming and solar fuel *** primary setup of the experimental platform consisted of a trough concentrating solar collector,chemical looping reforming reactors with indirect heat transfer,and associated auxiliary *** on the chemical looping redox cycle were conducted using nickel-based NiO/NiAl_(2)O_(4)as the OC under different direct normal irradiation(DNI)from 740 to 920 W/m^(2).Under irradiation at approximately 920 W/m^(2),the methane conversion initially increased to 92%before declining to 75%from 0 to 900 s and then to 2500 *** these conditions,the syngas concentration increased from 30%to 57%and the solar-to-fuel efficiency reached 59%.The oxygen transfer rate during the chemical looping redox cycle was also experimentally *** redox cycle experiments were conducted for 540 min of long-term operation to assess the duration and adaptability *** fractional oxidation can consistently return to almost 1.0 after each redox cycle,indicating strong reactivity and regenerability when exposed to different levels of *** reactivity of the chemical looping redox cycle during typical autumn and winter days was also investigated and *** study aimed to prove that this 10-kW parabolic trough reactor prototype can harness 500℃solar heat to drive efficient methane reforming,offering a promising avenue for solar fuel production.

关键词： solar fuel solar reactor chemical looping thermochemical redox cycle methane reforming

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Evaluation of Joint Information Environment Service Capability of Space-based Network Information system Based on ANP-Fuzzy Comprehensive Evaluation Method 10

Evaluation of Joint Information Environment Service Capabili...

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10th IEEE Joint International Information Technology and Artificial Intelligence Conference, ITAIC 2022

作者： Han, Chi Jian, Ping Xiong, Wei Fu, Jingyu Aerospace Information Institute Space Engineering University Beijing China Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China

ISBN: (数字)9781665422079

ISBN: (纸本)9781665422079

In the increasingly systematic and networked environment of aerospace equipment, the space-based information service capability is not only affected by the platform and payload capacity of the mission spacecraft, but also increasingly restricted by the network characteristics and network environment for space-based information acquisition. In this context, the joint information environment of the space-based network information system is constructed (JIESNIS). The service capability evaluation index system of JIESNIS is constructed pertinently. Analytic Network Process (ANP) and fuzzy comprehensive evaluation method are combined to evaluate the service capability of JIESNIS. Based on the background of the space-based network information system joint information environment support operation under the customized and active service mode, the simulation model is constructed. The proposed ANP-Fuzzy comprehensive evaluation method is adopted to evaluate the capability JIESNIS, meanwhile the effectiveness of the method is verified. © 2022 IEEE.

关键词： Information services

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A non-probabilistic reliability topology optimization method based on aggregation function and matrix multiplication considering buckling response constraints

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 321-336页

作者： Lei WANG Yingge LIU Juxi HU Weimin CHEN Bing HAN Institute of Solid Mechanics School of Aeronautic Science and EngineeringBeihang UniversityBeijing 100191China Aircraft and Propulsion Laboratory Ningbo Institute of TechnologyBeihang UniversityNingbo 315100Zhejiang ProvinceChina State Key Laboratory of Navigation and Safety Technology Shanghai Ship and Shipping Research InstituteShanghai 200135China National Engineering Research Center of Ship&Shipping Control System Shanghai Ship and Shipping Research InstituteShanghai 200135China

A non-probabilistic reliability topology optimization method is proposed based on the aggregation function and matrix *** expression of the geometric stiffness matrix is derived,the finite element linear buckling analysis is conducted,and the sensitivity solution of the linear buckling factor is *** a specific problem in linear buckling topology optimization,a Heaviside projection function based on the exponential smooth growth is developed to eliminate the gray *** aggregation function method is used to consider the high-order eigenvalues,so as to obtain continuous sensitivity information and refined structural *** cyclic matrix programming,a fast topology optimization method that can be used to efficiently obtain the unit assembly and sensitivity solution is *** maximize the buckling load,under the constraint of the given buckling load,two types of topological optimization columns are *** variable density method is used to achieve the topology optimization solution along with the moving asymptote optimization *** vertex method and the matching point method are used to carry out an uncertainty propagation analysis,and the non-probability reliability topology optimization method considering buckling responses is developed based on the transformation of non-probability reliability indices based on the characteristic ***,the differences in the structural topology optimization under different reliability degrees are illustrated by examples.

关键词： buckling topology optimization aggregation function uncertainty propagation analysis non-probabilistic reliability

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Spatio-temporal variations in ecological spaces and their ecological carrying status in China's mega-urban agglomerations

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Journal of Geographical Sciences 2022年第9期32卷 1683-1704页

作者： WANG Shihao HUANG Lin XU Xinliang LI Jiahui State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China University of Chinese Academy of Sciences Beijing100049China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China

The rapid expansion of China’s urban agglomerations in recent decades has resulted in over-occupied ecological spaces and increased ecological pressure that are restricting healthy regional *** paper examines the structure and characteristics of distribution of“production-living-ecological”spaces in five mega-urban agglomerations in China:beijing-Tianjin-Hebei(BTH),the Yangtze River Delta(YRD),Guangdong-Hong Kong-Macao Greater Bay Area(GBA),Chengdu-Chongqing(CY),and the middle reaches of the Yangtze River(MYR).We analyze spatial and temporal variations in the ecological spaces and factors influencing them from 1990 to 2020,and examine the comprehensive ecological carrying capacity and status of ecological spaces in the past 30 years based on the available water resources,regulation of water and air quality,and leisure and *** results show the following:(1)Urban agglomerations in different stages of formation and development represent varying area ratios of“ecological-production-living”*** modes of expansion and evolution of the living spaces are dominated by multi-center combinations as well as the spatial structure of ecological spaces,including barrier,compact,discrete,and fully enveloping spaces.(2)From 1990 to 2020,the area occupied by living spaces in urban agglomerations continued to increase significantly while that of spaces for ecological production *** in the GBA,ecological spaces have exhibited a trend of increase in area,especially in the past 10 *** area ratios and spatio-temporal variations in the“production-living-ecological”spaces indicate that the main functions of production and ecological spaces in mega-urban agglomerations have shifted from supply to regulation and culture,and reflect the transition from rapid urbanization to sustainable urbanization in China.(3)The comprehensive ecological carrying capacities of 78.6%,73.1%,54.5%,56.3%,and 25.8%of cities in BTH,YRD,GBA,CY and MYR are severely ove

关键词： mega-urban agglomerations “production-living-ecological”spaces ecological spaces ecological carrying capacity spatial and temporal variations

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A Valuable and Low-Budget Process Scheme of Equivalized 1 nm Technology Node Based on 2D Materials

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Nano-Micro Letters 2025年第8期17卷 294-305页

作者： Yang Shen Zhejia Zhang Zhujun Yao Mengge Jin Jintian Gao Yuhan Zhao Wenzhong Bao Yabin Sun He Tian College of Integrated Circuit Science and Engineering Shanghai Key Laboratory of Multidimensional Information ProcessingEast China Normal UniversityShanghai 200241People’s Republic of China Institute of Microelectronics and Beijing National Research Center for Information Science and Technology(BNRist) Tsinghua UniversityBeijing 100084People’s Republic of China State Key Laboratory of ASIC and System School of MicroelectronicsFudan UniversityShanghai 200433People’s Republic of China Shaoxin Laboratory Shaoxing 312000People’s Republic of China

Emerging two-dimensional(2D)semiconductors are among the most promising materials for ultra-scaled transistors due to their intrinsic atomic-level *** the stacking process advances,the complexity and cost of nanosheet field-effect transistors(NSFETs)and complementary FET(CFET)continue to *** 1 nm technology node is going to be based on Si-CFET process according to international roadmap for devices and systems(IRDS)(2022,https://***/),but not publicly confirmed,indicating that more possibilities still *** miniaturization advantage of 2D semiconductors motivates us to explore their potential for reducing process costs while matching the performance of next-generation nodes in terms of area,power consumption and *** this study,a comprehensive framework is built.A set of MoS2 NSFETs were designed and fabricated to extract the key parameters and *** then for benchmarking,the sizes of 2D-NSFET are scaled to a extent that both of the Si-CFET and 2D-NSFET have the same average device *** these conditions,the frequency of ultra-scaled 2D-NSFET is found to improve by 36%at a fixed power *** work verifies the feasibility of replacing silicon-based CFETs of 1 nm node with 2D-NSFETs and proposes a 2D technology solution for 1 nm nodes,i.e.,“2D eq 1 nm”*** the same time,thanks to the lower characteristic length of 2D semiconductors,the miniaturized 2D-NSFET achieves a 28%frequency increase at a fixed power ***,developing a standard cell library,these devices obtain a similar trend in 16-bit RISC-V *** work quantifies and highlights the advantages of 2D semiconductors in advanced nodes,offering new possibilities for the application of 2D semiconductors in high-speed and low-power integrated circuits.

关键词： Two-dimensional semiconductors 1 nm technology node Nanosheet field-effect transistors Complementary field-effect transistors Horizontal scaling

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Overvoltage Suppression Strategy Based on Active Control of Current for Half-Wave Commutated Modular Multilevel Converters 14

Overvoltage Suppression Strategy Based on Active Control of ...

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14th International Conference on Power and Energy systems, ICPES 2024

作者： Liu, Bao Xu, Yunfei Zhao, Guoliang Fu, Nan Jia, Chen China Electric Power Research Institute State Key Laboratory of Advanced Power Transmission Technology Beijing China Tsinghua University State Key Laboratory of Control and Simulation of Power System and Generation Equipment Beijing China Electric Power Research Institute State Grid Liaoning Electric Power Co. Ltd. Shenyang China

ISBN: (纸本)9798350391329

Flexible low-frequency AC transmission technology combines the advantages of 50 Hz AC transmission and DC transmission, and has good application scenarios. High voltage and large capacity AC/AC converters are the core equipment of flexible low-frequency AC transmission systems. The proposal of half-wave commutated modular multilevel converters effectively reduces the number of components and improves system economy. In view of this, this paper proposes an overvoltage suppression strategy for active control of inductor current, which effectively reduces the overvoltage level during commutation. The article first introduces the sparse topology and mathematical model of the half-wave commutated modular multilevel converters. Secondly, the mechanism of overvoltage generation is analyzed. Then, overvoltage suppression strategies are proposed. Finally, a PSCAD simulation model is built to verify the effectiveness and feasibility of the proposed method through simulation. © 2024 IEEE.

关键词： Flexible AC transmission systems

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Design of 3D-printed Cable Driven Humanoid Hand Based on Bidirectional Elastomeric Passive Transmission

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Chinese Journal of Mechanical engineering 2021年第4期34卷 225-235页

作者： Teru Chen Xingwei Zhao Guocai Ma Bo Tao Zhouping Yin State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Intelligent Manufacturing System Technology Beijing Institute of Electronic System EngineeringBeijing 100854China

Motion control of the human hand is the most complex part of the human *** has always been a challenge for a good balance between the cost,weight,responding speed,grasping force,finger extension,and dexterity of prosthetic *** solve these issues,a 3D-printed cable driven humanoid hand based on bidirectional elastomeric passive transmission(BEPT)is designed in this paper.A semi-static model of BEPT is investigated based on energy conservation law to analyze the mechanical properties of BEPT and a dynamical simulation of finger grasping is *** a good imitation of human hand and an excellent grasping performance,specific BEPT is selected according to human finger grasping *** advantage of BEPT based humanoid hand is that a good balance between the price and performance of the humanoid hand is *** proved that the designed prosthetic hand’s single fingertip force can reach 33 N and the fastest fingertip grasping speed realized 0.6 s/180°.It also has a good force compliance effect with only 430g’s *** can not only grab fragile objects like raw eggs and paper cup,but also achieve strong grasping force to damage metal *** humanoid hand has considerable application prospects in artificial prosthesis,human-computer interaction,and robot operation.

关键词： Humanoid hand Bidirectional elastomeric passive transmission Artificial prosthesis

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Field experimental study on the effect of thawed depth of frozen alpine meadow soil on rill erosion by snowmelt waterflow

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International Soil and Water Conservation Research 2024年第1期12卷 54-63页

作者： Ying Zheng Xiaonan Shi Fan Zhang Tingwu Lei Chen Zeng Xiong Xiao Li Wang Guanxing Wang State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100101China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing210098China College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China College of Geographic Science Hunan Normal UniversityChangsha410081China

Soil erosion by snow or ice melt waterflow is an important type of soil erosion in many high-altitude and high-latitude regions and is further aggravated by climate *** snowmelt waterflow erosion process is affected by soil freeze-thaws and is highly dynamically *** this study,a methodology was developed to conduct in situ field experiments to investigate the effects of the thawed depth of the frozen soil profile on snowmelt waterflow *** method was implemented on an alpine meadow soil slope at an altitude of 3700 m on the northeastern Tibetan *** erosion experiments involved five thawed soil depths of 0,10,30(35),50,and 80(100)mm under two snowmelt waterflow rates(3 and 5 L/min).When the topsoil was fully frozen or shallow-thawed(≤10 mm),its hydrothermal and structural properties caused a significant lag in the initiation of runoff and delayed soil erosion in the initial *** runoff and sediment concentration curves for fully frozen and shallow-thawed soil showed two-stage patterns characteristic of a sediment supply limited in the early stage and subject to hydrodynamic-controlled processes in the later ***,this effect did not exist where the thawed soil depth was greater than 30 *** deep-thawed cases(≥30 mm)showed normal hydrograph and sedigraph patterns similar to those of the unfrozen *** findings of this study are important for understanding the erosion rates of partially thawed soil and for improving erosion simulations in cold regions.

关键词： Snowmelt waterflow erosion Hillslope erosion process Soil freeze and thaw Runoff generation In situ experimental method

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Numerical simulation of Streamer Discharge in Transformer Oil Under Various Ionization Energies 19th

Numerical Simulation of Streamer Discharge in Transformer Oi...

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19th Annual Conference of China Electrotechnical Society, ACCES 2024

作者： Bao, Yanyan Liang, Shaobin Wang, Feng Zhang, Guangdong Chen, Jianning Zhou, Yuanxiang State Grid Gansu Electric Power Research Institute Lanzhou730070 China State Key Laboratory of Power System Operation and Control Beijing100084 China Department of Electrical Engineering Tsinghua University Beijing100084 China

ISBN: (纸本)9789819613786

Discharge in transformer oil is one of the primary causes of transformer failures. The physical mechanisms of oil discharges are not yet fully understood. Scholars have simulated the discharge process with electrodynamics model, but there is limited research on how the ionization energy, which changes due to various factors such as components and temperature of transformer oil, affect the streamer discharge characteristic. To improve the mechanism of discharge in transformer oil, this paper adopts an electrohydrodynamic model to study the impact of different ionization energies on the streamer discharge characteristics of transformer oil, including initiation voltage, discharge voltage, development speed, and electric field strength. When the ionization energy is between 6.1 eV and 8.1 eV, the initiation voltage and discharge voltage increase linearly with the ionization energy. Within the range of 7.1 eV to 8.1 eV, the time in the streamer accumulation phase increases exponentially with the ionization energy, while the streamer development speed decreases. © beijing Paike Culture Commu. Co., Ltd. 2025.

关键词： Electrohydrodynamics

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