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Design and dynamic analysis of integrated architecture for vibration energy harvesting including piezoelectric frame and mechanical amplifier

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Applied Mathematics and Mechanics(English Edition) 2021年第6期42卷 755-770页

作者： Xiangjian DUAN Dongxing CAO Xiaoguang LP Yongjun SHEN Beijing Institute of Structure and Environment Engineering Beijing 100076China Faculty of Materials and Manufacturing Bejing University of TechnologyBeijing 100124China Beijing Key Laboratory of Nonlinear V ibrations and Strength of Mechanical Structures Beijing 100124China State Key Laboratory of Mechanical Behavior and System Safety of Trafic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

Vibration energy harvesters(VEHs) can transform ambient vibration energy to electricity and have been widely investigated as promising self-powered devices for wireless sensor networks, wearable sensors, and applications of a micro-electro-mechanical system(MEMS). However, the ambient vibration is always too weak to hinder the high energy conversion efficiency. In this paper, the integrated frame composed of piezoelectric beams and mechanical amplifiers is proposed to improve the energy conversion efficiency of a VEH. First, the initial structures of a piezoelectric frame(PF) and an amplification frame(AF) are designed. The dynamic model is then established to analyze the influence of key structural parameters on the mechanical amplification factor. Finite element simulation is conducted to study the energy harvesting performance, where the stiffness characteristics and power output in the cases of series and parallel load resistance are discussed in detail. Furthermore, piezoelectric beams with variable cross-sections are introduced to optimize and improve the energy harvesting efficiency. Advantages of the PF with the AF are illustrated by comparison with conventional piezoelectric cantilever beams. The results show that the proposed integrated VEH has a good mechanical amplification capability and is more suitable for low-frequency vibration conditions.

关键词： vibration energy harvesting mechanical amplifier piezoelectric frame(PF) amplification frame(AF) variable cross-section beam

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An Efficient and High-Precision Aerodynamic Modeling Method for Hypersonic Vehicle Optimization Design

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Aerospace Science and Technology 2025年

作者： TieLin MA Pu XUE LuLu JIANG Xin PAN Gang CHEN School of Aeronautic Science and Engineering Beihang University Beijing 100191 China Institute of Unmanned System Beihang University Beijing 100191 China State Key Laboratory for Strength and Vibration of Mechanical Structures Shannxi Key Laboratory for Environment and Control of Flight Vehicle School of Aerospace Engineering Xi’an Jiaotong University Xi’an 710049 China

To address the challenges of nonlinear aerodynamic behavior, complex coupling effects, and high computational costs in hypersonic vehicle aerodynamic shape optimization, this study proposes an efficient and high-precision aerodynamic modeling approach. The proposed method introduces a Data Fusion Correction (DFC) strategy to construct aerodynamic datasets by combining high- and low-fidelity data, significantly reducing computational time while maintaining data accuracy. Additionally, a Double-Stage Fusion Surrogate (DFS) model is developed, integrating interpolation and regression techniques to enhance predictive accuracy for complex aerodynamic relationships. Validation results demonstrate that the proposed surrogate model achieves a maximum error of less than 2.5% compared to high-fidelity CFD results. By coupling the aerodynamic modeling framework with the NSGA-II optimization algorithm, this study successfully optimizes the aerodynamic shape of a hypersonic vehicle, achieving a 55% reduction in computational time compared to traditional methods. The optimized configurations satisfy design constraints and achieve significant improvements in aerodynamic performance, including a 9.13% reduction in drag coefficient and a 15.47% reduction in zero-angle-of-attack pitching moment coefficient. This research provides a computationally efficient and accurate aerodynamic modeling strategy for hypersonic vehicle optimization, offering a practical solution for future aerodynamic analysis and design.

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Identifiability Analysis of Load Model Parameters by Estimating Confidential Intervals

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CSEE Journal of Power and Energy systems 2023年第5期9卷 1666-1675页

作者： Xinran Zhang Chao Lu Ying Wang Qiantu Ruan Hongbo Ye Weihong Wang the School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China. the State Key Laboratory of Control and Simulation of Power System and Generation Equipment Tsinghua UniversityBeijing 100084China School of Technology Beijing Forestry UniversityBeijing 100083China the State Grid Shanghai Electric Power Company Shanghai 200122China

The identification of load model parameters from practical measurement data has become an essential method to build load models for power system simulation,analysis and *** practical situations,the accuracy of the load model parameters identification results is impacted by data quality and measurement accuracy,which leads to the problem of *** this paper,an identifiability analysis methodology of load model parameters,by estimating the confidential intervals(CIs)of the parameters,is *** load model structure and the combined optimization and regression method to identify the parameters are first ***,the definition and analysis method of identifiability are *** CIs of the parameters are estimated through the profile likelihood method,based on which a practical identifiability index(PII)is defined to quantitatively evaluate ***,the effectiveness of the proposed analysis approach is validated by the case study results in a practical provincial power *** results show that the impact of various disturbance magnitudes,measurement errors and data length can all be reflected by the proposed ***,the proposed PII can provide guidance in data length selection in practical load model identification situations.

关键词： Confidential interval Load modeling parameter estimation practical identifiability

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Area-oriented coordinated trajectory planning of dual-arm space robot for capturing a tumbling target

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Chinese Journal of Aeronautics 2019年第9期32卷 2151-2163页

作者： Wenfu XU Lei YAN Zhonghua HU Bin LIANG School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen 518055China State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China Department of Automation Tsinghua UniversityBeijing 100084China

The growing amount of space debris poses a threat to operational spacecraft and the long-term sustainability of activities in outer space. According to the orbital mechanics, an uncontrolled space object will be tumbling, bringing great challenge to capture and remove it. In this paper, a dual-arm coordinated ‘‘Area-Oriented Capture'(AOC) method is proposed to capture a non-cooperative tumbling target. Firstly, the motion equation of the tumbling target is established, based on which, the dynamic properties are analyzed. Then, the ‘‘Area-Oriented Capture'concept is presented to deal with the problem of large pose(position and attitude) deviation and tumbling motion. An area rather than fixed points/devices is taken as the object to be tracked and captured. As long as the manipulators’ end-effectors move to a specified range of the objective areas(not fixed points on the target, but areas), the target satellite will be hugged by the two *** last, the proposed method and the traditional method(i.e. fixed-point oriented capture method)are compared and analyzed through simulation. The results show that the proposed method has larger pose tolerance and takes shorter time for capturing a tumbling target.

关键词： Area-oriented capture Dual-arm coordination Space debris removal Space robot Tumbling target capturing

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key Technique of Constructing Collaborating Environment Based on OPENMBEE 6

Key Technique of Constructing Collaborating Environment Base...

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6th IEEE International Conference on Computer and Communications, ICCC 2020

作者： Xue, Junjie Zhou, Junhua Shi, Guoqiang Jiang, Yanhong Xu, Shuying Quan, Hongyan State Key Laboratory of Intelligent Manufacturing System Technology Beijing Institute of Electronic System Engineering Beijing China Science and Technology on Space System Simulation Laboratory Beijing Simulation Center Beijing China School of Software Engineering East China Normal University Shanghai China School of Computer Science and Technology East China Normal University Shanghai China

ISBN: (纸本)9781728186351

With the development of integrated design and manufacturing technology, it is necessary to consider how to integrate a variety of modeling tools in the procedure of complex product design driven by the model-centric conception. In this work, we explored the development technology of multi-tool integration based on the Open Model Based engineering Environment (OpenMBEE). We provide a multi-tool integration system solution, in which the integration schemes under different environments of LAN and virtual machine are designed, and the system scheme of multi-tool integration is also studied. From the idea of model design conception, we integrate the requirement analysis tools Cameo. On the basis, Model Management system (MMS) and View Editor(VE), as well as the specific model analysis tool MATLAB and 3D visual simulation tool Creo are also integrated seamlessly. The effectiveness of the proposed integration strategies is verified by some practical instances. That is verified that our study can provide an effective design idea for complex production. © 2020 IEEE.

关键词： MATLAB

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Preparation and Photocatalytic Property of Porous TiO_2 Film with Net-like Framework

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Chemical Research in Chinese Universities 2009年第1期25卷 95-97页

作者： XU Rong-guo YAO Jian-xi LAI Xiao-yong MAO Dan XING Chao-jian WANG Dan State Key Laboratory of Multi-phase Complex System Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 P. R. China Graduate University of Chinese Academy of Sciences Beijing 100049 P. R. China

By the UV-curing method, a porous TiO2 film with net-like framework has been prepared. The characterization results of the porous TiO2 film by means of SEM, TEM, XRD, and N2 adsorption-desorption analysis show that the net-like framework of the porous TiO2 film is composed of TiO2 nanoparticles, forming three dimensional porous structure. The porous TiO2 film exhibits higher photocatalytic activity for the degradation of methylene blue（MB） dye compared with the conventional dense TiO2 film.

关键词： UV-curing TiO2 Porous film Photocatalytic activity

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Development of a cable-driven redundant space manipulator with large bending angle by combining quaternion joints and segmented coupled linkages mechanism

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Chinese Journal of Aeronautics 2023年第11期36卷 483-499页

作者： Taiwei YANG Jian HUANG Wenfu XU Ke SHAO Bin LIANG School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen 518055China State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China Department of Automation Tsinghua UniversityBeijing 100854China

A cable-driven redundant manipulator has significant potential in confined space applications, such as environmental exploration, equipment monitoring, or maintenance. A traditional design requires 3N driving motors/cables to supply 2N degrees of freedom(DOF) movement *** number of motors is 1.5 times that of the joints’ DOF, increasing the hardware cost and the complexity of the kinematics, dynamics, and control. This study develops a novel redundant space manipulator with decoupled cable-driven joints and segmented linkages. It is a 1680 mm continuum manipulator with eight DOF, consisting of four segmented linkages driven by eight motors/pairs of cables. Each segment has two equivalent DOF, which are realized by four quaternion joints synchronously driven by two linkage cables. The linkage cables of adjacent joints are symmetrically decoupled and offset at 180°. This design allows equal-angle movement of all the joints of each segment. Moreover, each decoupling driving mechanism is designed based on a pulley block composed of two fixed and movable pulleys. The two movable pulleys realize the opposite but equidistant motions of the two driving cables, i.e., pulling and loosening, assuring symmetrical movements of the two driving cables of each segment. Consequently, the equivalent 2N-DOF joints are driven only by 2N motors, significantly reducing the hardware cost and simplifying the mapping relationship between the motor angle/cable length and the joint angle. Furthermore, the bending range of each segment could reach 360°, which is three times that of a traditional design. Finally, a prototype has been developed and experimented with to verify the performance of the proposed mechanism and the corresponding algorithms.

关键词： Cable-driven Mechanism design Redundant manipulators Segmented linkages Kinematics

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The impact of the atmospheric turbulence-development tendency on new particle formation: a common finding on three continents

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National Science Review 2021年第3期8卷 140-150页

作者： Hao Wu Zhanqing Li Hanqing Li Kun Luo Yuying Wang Peng Yan Fei Hu Fang Zhang Yele Sun Dongjie Shang Chunsheng Liang Dongmei Zhang Jing Wei Tong Wu Xiaoai Jin Xinxin Fan Maureen Cribb Marc L.Fischer Markku Kulmala Tuukka Pet?j? State Key Laboratory of Remote Sensing Science College of Global Change and Earth System ScienceBeijing Normal University ESSIC and Department of Atmospheric Science University of MarylandCollege Park State Key Laboratory of Clean Energy Utilization Zhejiang University School of Atmospheric Physics Nanjing University of Information Science and Technology Meteorological Observation Center China Meteorological Administration State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Lawrence Berkeley National Laboratory Institute for Atmospheric and Earth System Research/Physics Faculty of ScienceUniversity of Helsinki Aerosol and Haze Laboratory Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Joint International Research Laboratory of Atmospheric and Earth System Sciences School of Atmospheric Sciences Nanjing University

A new mechanism of new particle formation(NPF) is investigated using comprehensive measurements of aerosol physicochemical quantities and meteorological variables made in three continents,including beijing,China;the Southern Great Plains site in the USA;and SMEAR Ⅱ Station in Hyytiala,Finland.D espite the considerably different emissions of chemical species among the sites,a common relationship was found between the characteristics of NPF and the stability *** stability parameter(ζ=Z/L,where Z is the height above ground and L is the Monin-Obukhov length) is found to play an important role;it drops significantly before NPF as the atmosphere becomes more unstable,which may serve as an indicator of nucleation *** the atmosphere becomes unstable,the NPF duration is closely related to the tendency for turbulence development,which influences the evolution of the condensation ***,the unstable atmosphere may dilute pre-existing particles,effectively reducing the condensation sink,especially at coarse mode to foster *** new mechanism is confirmed by model simulations using a molecular dynamic model that mimics the impact of turbulence development on nucleation by inducing and intensifying homogeneous nucleation events.

关键词： new particle formation turbulence development molecular dynamic

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Dynamic Manning’s roughness coefficients for hydrological modelling in basins

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Hydrology Research 2018年第5期49卷 1379-1395页

作者： Ye, Aizhong Zhou, Zheng You, Jinjun Ma, Feng Duan, Qingyun State Key Laboratory of Earth Surface and Ecological Resources Institute of Land Surface System and Sustainable Development Faculty of Geographical Science Beijing Normal University Beijing100875 China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research Beijing100038 China

Manning’s roughness coefficient (n) has a significant impact on routing in hydrological models. However, computational methods for dynamic roughness coefficients are of little concern in current research. Few studies have produced spatial-temporal distributions of the roughness coefficients in basins. In this study, a formula to calculate the n value was established based on a statistical analysis of estimated n values by Manning’s formula. The routing model of a distributed hydrological model was then improved using the new formula to calculate n. The roughness coefficient is not a constant;instead, it changes dynamically with changes in water depth and vegetation in the improved hydrological model. The improved model was applied to the Yellow River basin. The results show that using dynamic n can improve the streamflow simulation of hydrological models, especially on slopes. The dynamic spatial-temporal distribution of n can now be used in other models. © IWA Publishing 2018.

关键词： Climate models

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Vertical distribution of aerosol optical properties based on aircraft measurements over the Loess Plateau in China

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Journal of Environmental Sciences 2015年第8期27卷 44-56页

作者： Junxia Li Xingang Liu Liang Yuan Yan Yin Zhanqing Li Peiren Li Gang Ren Lijun Jin Runjun Li Zipeng Dong Yiyu Li Junmei Yang Weather Modification Office of Shanxi Province Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science and Technology State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University College of Global Change and Earth System Science Beijing Normal University Meteorological Institute of Shaanxi Province

Vertical distributions of aerosol optical properties based on aircraft measurements over the Loess Plateau were measured for the first time during a summertime aircraft campaign, 2013 in Shanxi, China. Data from four flights were analyzed. The vertical distributions of aerosol optical properties including aerosol scattering coefficients（σsc）, absorption coefficients（σab）,Angstr？m exponent（α）, single scattering albedo（ω）, backscattering ratio（βsc）, aerosol mass scattering proficiency（Q sc） and aerosol surface scattering proficiency（Q sc′） were obtained. The mean statistical values of σsc were 77.45 Mm-1（at 450 nm）, 50.72 Mm-1（at 550 nm）, and32.02 Mm-1（at 700 nm）. The mean value of σab was 7.62 Mm-1（at 550 nm）. The mean values ofα, βsc and ω were 1.93, 0.15, and 0.91, respectively. Aerosol concentration decreased with altitude. Most effective diameters（ED） of aerosols were less than 0.8 μm. The vertical profiles of σsc,, α, βsc, Q sc and Q sc′ showed that the aerosol scattering properties at lower levels contributed the most to the total aerosol radiative forcing. Both α and βsc had relatively large values, suggesting that most aerosols in the observational region were small particles. The mean values of σsc, α, βsc, Q sc, Q sc′, σab and ω at different height ranges showed that most of the parameters decreased with altitude. The forty-eight hour backward trajectories of air masses during the observation days indicated that the majority of aerosols in the lower level contributed the most to the total aerosol loading, and most of these particles originated from local or regional pollution emissions.

关键词： Vertical distribution Optical properties Aircraft measurements The Loess Plateau

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