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Design and development of a five-axis machine tool with high accuracy,stiffness and efficiency for aero-engine casing manufacturing

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Chinese Journal of Aeronautics 2022年第4期35卷 485-496页

作者： Yutian WANG Dong WANG Shizhen ZHANG Zihan TANG Liping WANG Yanmin LIU State Key Laboratory of Tribology and Institute of Manufacturing Engineering Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Beijing Key Lab of Precision Ultraprecision Manufacturing Equipment and Control Beijing 100084China Beijing Precision Machinery&Engineering Research Co.LTD Beijing 101312China Beijing Institute of Control Engineering Beijing 100094China

In order to satisfy the machining requirements of aero-engine casing in modern aviation industry, this paper investigates three main issues during the design and development process of a five-axis machine tool with high accuracy, stiffness and efficiency, including whole structure design,key components design, and supporting stiffness design. First, an appropriate structure of five-axis machine tool is determined considering the processing characteristics of aero-engine casing. Then, a dual drive swing head and a compact motorized spindle are designed with enough drive capability and stiffness, and related structure, assembly method, cooling technology, and performance simulation are given in detail. Next, a design method of supporting stiffness of guide is proposed through the deformation prediction of the spindle end. Based on above work, a prototype of machine tool is developed, and some experiments are carried out, including performance tests of swing head and motorized spindle, and machining of a simulated workpiece of aero-engine casing. All experimental results show that the machine tool has satisfactory accuracy, stiffness and efficiency, which meets the machining requirements of aero-engine casing. The main work can be used as references for engineers and technicians, which are meaningful in practice.

关键词： Aero-engine casing manufacturing Compact motorized spindle Dual drive swing head Five-axis machine tool Supporting stiffness

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Federated Intelligence for Intelligent Vehicles

IEEE Transactions on Intelligent Vehicles

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IEEE Transactions on Intelligent Vehicles 2024年第5期9卷 1-5页

作者： Zhang, Weishan Zhang, Baoyu Jia, Xiaofeng Qi, Hongwei Qin, Rui Li, Juanjuan Tian, Yonglin Liang, Xiaolong Wang, Fei-Yue School of China University of Petroleum Qingdao China Department of Data Management Big Data Centre Beijing Beijing China Technology Company Beijing China State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of Automation Chinese Academy of Sciences Beijing China Faculty of Innovation Engineering Macau University of Science and Technology Macao China State Key Laboratory for Management and Control of Complex Systems Institute of Automation Chinese Academy of Sciences Beijing China

This letter is a brief summary of a series of IEEE TIV's decentralized and hybrid workshops (DHWs) on Federated Intelligence for Intelligent Vehicles. The discussed results are: 1) Different scales of large models (LMs) can be federated and deployed on IVs, and three types of federated collaboration between large and small models can be adopted for IVs. 2) Federated fine-tuning of LMs is beneficial for IVs data security. 3) The sustainability of IVs can be improved through optimizing existing models and continuous learning using federated intelligence. 4) LM-enhanced knowledge can make IVs smarter. IEEE

关键词： Intelligent vehicle highway systems

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Interference Elimination and Kinematic Optimization of a 5-DoF Fully Parallel Mechanism 1

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24th IFToMM China International Conference on Mechanism and Machine Science and engineering, IFToMM CCMMS 2024

作者： Xie, Zenghui Wang, Hanxin Xie, Fugui Liu, Xin-Jun Tsinghua University Beijing100084 China State Key Laboratory of Tribology in Advanced Equipment Tsinghua University Beijing100084 China School of Mechatronics Engineering Harbin Institute of Technology Heilongjiang Harbin150001 China

ISBN: (数字)9789819614677

ISBN: (纸本)9789819614660

Featured by the potential characteristics of high precision and high stiffness, parallel kinematic mechanisms (PKMs) have great application prospects in the field of precision machining. To develop a high-performance parallel equipment, dimension optimization is a key step. Due to the complex structure with multiple kinematic limbs and passive joints, the change of dimensional parameters may simultaneously influence kinematic performance and engineering feasibility, which makes the dimension optimization of PKMs a challenging issue. In this paper, the motion and force transmission and constraint indices are adopted to evaluate the kinematic performance. Further, all types of possible interferences that influence the engineering feasibility are modeled, and corresponding evaluation indices are established. Finally, the kinematic performance and feasibility evaluation indices are considered together to optimize the mechanism. By virtue of an evolutionary algorithm, a set of feasible dimension parameters of the mechanism is obtained. The results lay the foundation for the development of a 5-DoF Fully Parallel Robot. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.

关键词： Precision engineering

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Atmospheric environment monitoring technology and equipment in China:A review and outlook

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Journal of Environmental Sciences 2023年第1期123卷 41-53页

作者： Youwen Sun Ting Yang Huaqiao Gui Xin Li Weigang Wang Jun Duan Shushuai Mao Hao Yin Bin Zhou Jianlei Lang Haijin Zhou Cheng Liu Pinhua Xie Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHFIPSChinese Academy of SciencesHefei 230031China Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of ChemistryChinese Academy of SciencesBeijing 100190China Key Laboratory of Beijing on Regional Air Pollution Control College of Environmental&Energy EngineeringBeijing University of TechnologyBeijing 100124China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes University of Science and Technology of ChinaHefei 230026China Anhui Province Key Laboratory of Polar Environment and Global Change University of Science and Technology of ChinaHefei 230026China

Accurate monitoring of the atmospheric environment and its evolution are important for understanding the sources,chemical mechanisms,and transport processes of air pollution and carbon emissions in China,and for regulatory and control *** study gives an overview of atmospheric environment monitoring technology and equipment in China and summarizes the major achievements obtained in recent *** has made great progress in the development of atmospheric environment monitoring technology and equipment with decades of *** manufacturing level of atmospheric environment monitoring equipment and the quality of products have steadily improved,and a technical&production system that can meet the requirements of routine monitoring activities has been *** is expected that domestic atmospheric environment monitoring technology and equipment will be able to meet future demands for routine monitoring activities in China and provide scientific assistance for addressing air pollution problems.

关键词： Atmospheric pollution Atmospheric environment Atmospheric monitoring Environmental instrument

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Cu-doped SnO_(2)/rGO nanocomposites for ultrasensitive H2S detection at low temperature

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Microsystems & Nanoengineering 2023年第3期9卷 61-71页

作者： Tingting Chen Jianhai Sun Ning Xue Wen Wang Zongchang Luo Qinqin Liang Tianye Zhou Hao Quan Haoyuan Cai Kangsong Tang Kaisheng Jiang State Key Laboratory of Transducer Technology Aerospace Information Research InstituteChinese Academy of Sciences100194 BeijingChina School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of Sciences100049 BeijingChina State Key Laboratory of Acoustics Institute of AcousticsChinese Academy of Sciences100190 BeijingChina Guangxi Key Laboratory of Intelligent Control and Maintenance of Power Equipment School of Electronic EngineeringGuangxi UniversityNanning 530004 GuangxiChina Electric Power Research Institute of Guangxi Power Grid Co. Ltd.Nanning 530013 GuangxiChina

Hydrogen sulfide(H_(2)S)detection remains a significant concern and the sensitivity,selectivity,and detection limit must be balanced at low ***,we utilized a facile solvothermal method to prepare Cu-doped SnO_(2)/rGO nanocomposites that have emerged as promising candidate materials for H_(2)S *** of the Cu-SnO_(2)/rGO was carried out to determine its surface morphology,chemical composition,and crystal *** optimal sensor response for 10 ppm H_(2)S was~1415.7 at 120℃,which was over 320 times higher than that seen for pristine SnO_(2)CQDs(R_(a)/R_(g)=4.4)at 280℃.Moreover,the sensor material exhibited excellent selectivity,a superior linear working range(R^(2)=0.991,1-150 ppm),a fast response time(31 s to 2 ppm),and ppb-level H_(2)S detection(R_(a)/R_(g)=1.26 to 50 ppb)at 120℃.In addition,the sensor maintained a high performance even at extremely high humidity(90%)and showed outstanding long-term *** superb H_(2)S sensing properties were attributed to catalytic sensitization by the Cu dopant and a synergistic effect of the Cu-SnO_(2)and rGO,which offered abundant active sites for O_(2)and H_(2)S absorption and accelerated the transfer of electrons/holes.

关键词： stability. selectivity attributed

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Feature of water: A practical concept in water reuse

Water Cycle

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Water Cycle 2025年 6卷 300-305页

作者： Chen, Xiao-Wen Xu, Yu-Qing Wang, Wen-Long Huang, Nan State Key Laboratory of Regional Environment and Sustainability Key Laboratory of Microorganism Application and Risk Control Ministry of Ecology and Environment School of Environment Tsinghua University Beijing100084 China Key Laboratory of Microorganism Application and Risk Control of Shenzhen Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety Institute of Environment and Ecology Tsinghua Shenzhen International Graduate School Tsinghua University Shenzhen518055 China Department of Environmental Engineering Faculty of Environment and Life Beijing University of Technology Beijing100124 China

The increasing stringency of standards has highlighted challenges in high-standard wastewater treatment and water reuse. Current water quality assessment primarily relies on bulk properties like chemical oxygen demand (COD) and biological oxygen demand (BOD), which fail to capture the intricate characteristics of wastewater contaminants. The novel concept of "feature of water", a multidimensional assessment system encompassing four primary indicators: quantitative concentration, compositional characteristics, transformation potential, and toxicological effects, is applied in the study. Unlike conventional linear approaches, feature of water provides a holistic perspective on wastewater composition, examining pollutant variations across temporal and spatial dimensions. Applications of the feature of water concept include the identification of refractory pollutants, evaluation of treatment processes, and the design of tailored treatment technologies. Case studies demonstrate its effectiveness in improving water treatment efficiency, reducing operational costs, and mitigating ecological risks. By transitioning from traditional linear water quality evaluation to a systems-based approach, the feature of water provides a robust methodology to meet the demands of high-standard wastewater treatment and water reuse, ensuring environmental sustainability and public health protection. © 2025 The Authors

关键词： Water recycling

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Passive activity enhances residual control ability in patients with complete spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2337-2347页

作者： Yanqing Xiao Mingming Gao Zejia He Jia Zheng Hongming Bai Jia-Sheng Rao Guiyun Song Wei Song Xiaoguang Li Beijing Key Laboratory for Biomaterials and Neural Regeneration Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Department of Rehabilitation Evaluation China Rehabilitation Research CenterBeijingChina Cardiac Center Beijing Children’s HospitalCapital Medical UniversityBeijingChina The State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijingChina Department of Rehabilitation Engineering China Rehabilitation Science InstituteBeijingChina

Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury ***,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface *** this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord *** patients with chronic complete thoracic spinal cord injury were *** electromyography data from eight major leg muscles were acquired and compared before and after the passive activity *** results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of *** the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically *** findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.

关键词： complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task

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Energy-Consumption Optimization control for Lunar Rover's Travel with Torque-Distribution-strategy in Rear Wheels

Energy-Consumption Optimization Control for Lunar Rover's Tr...

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2024 IEEE International Conference on control Science and Systems engineering, ICCSSE 2024

作者： Li, Delun Cao, Jianfei Chen, Yiliang Xie, Zongwu Harbin Institute of Technology State Key Laboratory of Robotics and System Harbin China Beijing Institute of Spacecraft System Engineering Beijing Key Laboratory of Intelligent Space Robotic Systems Technology and Applications Beijing China

ISBN: (纸本)9798331517199

In anticipation of future extensive lunar surface operations, lunar rovers are required to advance towards higher speeds and improved energy conservation. When traveling at high speeds on the lunar surface, the vehicle's energy expenditure is greatly amplified by the influence of the terrain, particularly in conditions where driving and steering are coupled. This paper proposes an energy-saving control strategy for lunar rovers that employs dynamic rear-axle torque distribution, with the goal of optimizing transient energy consumption during travel. To tackle the challenge of non-differentiable functions within the optimization objectives, we suggest using a zeroth-order gradient optimization method for resolution, dynamically constraining the range of control parameters to fulfill the dynamic torque distribution objectives as needed for the task. The energy-saving control effectiveness of the algorithm has been confirmed through simulation, demonstrating a minimum energy-saving ratio of at least 4%, which increases to over 11% as the speed level rises, offering a valuable technical solution for the energy optimization of lunar rovers. © 2024 IEEE.

关键词： Rovers

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Efficient optimization method for variable-specific-impulse low-thrust trajectories with shutdown constraint

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Science China(Technological Sciences) 2022年第3期65卷 581-594页

作者： JIA FeiDa QIAO Dong HAN HongWei LI XiangYu School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Autonomous Navigation and Control for Deep Space Exploration Ministry of Industry and Information TechnologyBeijing 100081China

This paper develops a sequential convex programming(SCP)-based method to solve the minimum-fuel variable-specific-impulse low-thrust transfer problem considering shutdown constraint,with emphasize on improving the computational *** variable parameter engine is more applicable for many low-thrust scenarios,therefore,both a continuously variable model and a ladder variable model are ***,the original problem is convexified by processing the constraint feasible domain,which is composed of the nonlinear dynamic equations and second-order equality constraint,into convex ***,the approximation is generated to close the optimal solution of the low-thrust problem by iteratively solving the convexified ***,the switching self-detection and adaptive node refinement methods are presented,which can improve the accuracy of the solution and accelerate the convergence during the approximation process and is especially necessary and effective in the scenarios with shutdown *** numerical simulations,the comparison with the homotopic approach shows that the proposed method only needs 4%computational time as that of the homotopic approach,and two variable-specificimpulse examples further demonstrate the effectiveness and efficiency of the proposed method.

关键词： low-thrust trajectory variable-specific-impulse shutdown constraint sequential convex programming switching self-detection and adaptive node refinement

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Design and Verification of mK Temperature Fluctuation control for Gravity Gradiometer 1

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10th International Conference on Signal and Information Processing, Network and Computers, ICSINC 2022

作者： Liu, Wei Zhou, Yupeng Li, Tinghao Beijing Key Laboratory for Space Thermal Control Technology Beijing Institute of Spacecraft System Engineering Beijing China

ISBN: (数字)9789811999680

ISBN: (纸本)9789811999673

Aiming at the requirement of high temperature stability of 10 mK/200 s of the gradiometer, a thermal control design is taken with the establishment of component-level resistance-capacitance filtering network, system-level enhanced thermal insulation design and high precision temperature control technology. The thermal analysis and the thermal balance test results show that the temperature stability of the gradiometer is lower than 8 mK/200 s and meet the required precision. The design provides a reference for the thermal control design of the other parts that require high-precision and high-temperature stability. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Thermal insulation

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