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2019 IEEE International Conference on Unmanned Systems, ICUS 2019

作者： Shao, Xingling Tian, Biao Li, Dongguang Ministry of Education North University of China School of Instrument and Electronics North University of China Key Laboratory of Instrumentation Science Dynamic Measurement Taiyuan030051 China Beijing Institute of Technology Science and Technology on Electromechanical Dynamic Control Laboratory Beijing10081 China

ISBN: (纸本)9781728137926

This paper presents an neural dynamic surface containment control design for multiple quadrotors with uncertainties, such that the followers can be driven into the convex hull constituted by multiple dynamic leaders. To facilitate the control design, the quadrotor dynamics is decomposed into translational and rotational subsystems. For each subsystem, in order to enable smooth and rapid learning of unknown system uncertainties and reduce the computational load in traditional neural network (NN), the estimation errors, instead of tracking errors, are used to regulate NN weights and only one NN learning parameter is required for adaptive neural approximation with the aid of minimal learning parameter (MLP), which is more feasible for real-time implementation. Additionally, dynamic surface control (DSC) technique is introduced to extract the time derivative of virtual control laws, and thus the issue of "explosion of complexity" can be circumvented. Finally, the stability analysis is established. Simulation results illustrate the effectiveness and superiority of the proposed control scheme. © 2019 IEEE.

关键词： Real time control

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Measuring System Of Internal Charges In Electron Irradiated Spacecraft’s Insulating Medium

Measuring System Of Internal Charges In Electron Irradiated ...

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IEEE International Conference on Unmanned Systems (ICUS)

作者： Yue Feng Xusong Tang Yanhui Han Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical Engineering Beijing Institute of Technology Beijing China Beijing Orient Institute of Measurement& Test Beijing China

ISBN: (数字)9781728180250

ISBN: (纸本)9781728180267

The accumulation of internal charge in the insulating medium caused by the high-energy charged particles has been one of the important factors threatening the safety of spacecrafts. As the spacecraft's orbital flight time and flight height increase, the internally charged effect of its insulating medium becomes more and more serious. In this work, we designed an internal charge distribution measuring system for an insulating medium under electron irradiation, based on the acoustic pulse method. The system could measure the internal charge of the dielectric material without contacting between the sample and the excitation unit. Furthermore, the internal charge measurements were performed on three kinds of typical spacecraft insulation medium materials (polyimide (PI), low-density polyethylene (LDPE), and polytetrafluoroethylene (PTFE)) under electron irradiation. The internal charge and internal electric field distribution of the specimens were obtained. This system is more suitable for studying the internal charge accumulation behavior of spacecraft's insulating medium in space environment.

关键词： Radiation effects Polyimides Polyethylene Data processing Charge measurement

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Tailoring the Anomalous Hall Effect in Van Der Waals Ferromagnet Fe3gete2

SSRN

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SSRN 2024年

作者： Wu, Kaile Wang, Qin Wang, Junshan Jiang, Jiaolin Zhao, Tian Zhao, Dong Han, Dan Quan, Zhiyong Ma, Zongmin Wang, Haomin Sang, Shengbo Ge, Yang Shanxi Key Laboratory of Micro Nano Sensors & Artificial Intelligence Perception College of Electronic Information and Optical Engineering Taiyuan University of Technology Taiyuan030024 China Key Lab of Advanced Transducers and Intelligent Control System The Ministry of Education Taiyuan University of Technology Taiyuan030024 China College of Materials Science and Engineering Taiyuan University of Technology Taiyuan030024 China Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education School of Chemistry and Materials Science Shanxi Normal University Taiyuan030031 China State Key Laboratory of Dynamic Measurement Technology North University of China Shanxi Taiyuan030051 China School of Semiconductor and Physics North University of China Shanxi Taiyuan030051 China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai200050 China Shanxi Research Institute of 6D Artificial Intelligence Biomedical Science Taiyuan030024 China

Two-dimensional van der Waals magnetic materials have shown fascinating natural ferromagnetic properties at the atomic level, which has great potential in fields of low power spintronics, quantum computing and optical communication. Herein, the ferromagnetism and magnetic anisotropy of bulk Fe3GeTe2 (FGT) were investigated, and the testing results indicate a pronounced vertical magnetic anisotropy below the Curie temperature (Tc=165 K) of FGT. In addition, the anomalous Hall effect of FGT nanoflakes was studied at various temperatures and thicknesses by standard Hall bar device in detail. The results show the anomalous Hall resistance (0.764 Ω at 20 K decreased to 0.332 Ω at 140 K) and the obvious rectangular magnetic hysteresis rings below Tc (165 K). Furthermore, we calculated the carrier concentration (2.5×1022 cm-3 at 20K) and mobility (13.3 cm2/(v·s) at 20K) under large magnetic field (-6 T~6 T). Particularly, we demonstrated that the strong tailoring ability of the anomalous Hall effect for FGT-based magnetoelectric transport devices comes form the regulation of magnetic moment by sample thickness and magnetic field angle. The above experimental results verify that FGT is expected to be a prime candidate material for ultrathin 2D spintronic devices to the next generation. © 2024, The Authors. All rights reserved.

关键词： Germanium alloys

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Discovery of the high-entropy carbide ceramic topological superconductor candidate (Ti0.2Zr0.2Nb0.2Hf0.2Ta0.2)C

arXiv

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arXiv 2023年

作者： Zeng, Lingyong Wang, Zequan Song, Jing Lin, Gaoting Guo, Ruixin Luo, Si-Chun Guo, Shu Li, Kuan Yu, Peifei Zhang, Chao Guo, Wei-Ming Ma, Jie Hou, Yusheng Luo, Huixia School of Materials Science and Engineering State Key Laboratory of Optoelectronic Materials and Technologies Key Lab of Polymer Composite & Functional Materials Guangzhou Key Laboratory of Flexible Electronic Materials Wearable Devices Sun Yat-Sen University Guangzhou510275 China Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices Center for Neutron Science and Technology School of Physics Sun Yat-Sen University Guangzhou510275 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing100190 China Key Laboratory of Artificial Structures and Quantum Control Shenyang National Laboratory for Materials Science School of Physics and Astronomy Shanghai Jiao Tong University Shanghai200240 China Shenzhen Institute for Quantum Science and Engineering Southern University of Science and Technology Shenzhen518055 China International Quantum Academy Shenzhen518048 China School of Electromechanical Engineering Guangdong University of Technology Guangzhou510006 China Wuhan National High Magnetic Field Center Huazhong University of Science and Technology Wuhan430074 China

High-entropy ceramics (HECs) are solid solutions of inorganic compounds with one or more Wyckoff sites shared by equal or near-equal atomic ratios of multi-principal elements. Material design and property tailoring possibilities emerge from this new class of materials. Here, we report the discovery of superconductivity around 2.35 K and topological properties in the (Ti0.2Zr0.2Nb0.2Hf0.2Ta0.2)C high-entropy carbide ceramic (HECC), which has not been observed before in any of the investigated HECC. Density functional theory calculations showed that six type-II Dirac points exist in (Ti0.2Zr0.2Nb0.2Hf0.2Ta0.2)C, which mainly contributed from the t2g orbitals of transition metals and the p orbitals of C. Due to the stability of the structure, we also observed robust superconductivity under pressure in this HEC superconductor. This study expands the physical properties of HECs, which may become a new material platform for superconductivity research, especially for studying the coupling between superconductivity and topological physics. Copyright © 2023, The Authors. All rights reserved.

关键词： Carbides

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Calculation model for kinetic energy and rock burst risk evaluation method during roadway excavation

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International Journal of Mining science and technology 2025年第05期 677-690页

作者： Yunliang Tan Yan Tan Weiyao Guo Bo Li Shudong He Lei Zhang Yujiang Zhang Qiuyuan Zhang College of Energy and Mining Engineering Shandong University of Science and Technology Shandong Key Laboratory of Intelligent Prevention and Control of Dynamic Disaster in Deep Mines Shandong University of Science and Technology School of Civil Engineering Tongji University China Coal Technology&Engineering Group Chongqing Research Institute College of Coal Engineering Shanxi Datong University College of Mining Engineering Taiyuan University of Technology Yuanbaoshan Open-pit Coal Mine Inner Mongolia Pingzhuang Coal Group Co.Ltd.

The accumulation and release of deformation energy within the rock mass of a roadway are primary contributors to the occurrence of rock bursts. This study introduces a calculation model for the kinetic energy generated during roadway excavation, which is based on the fracture and energy states of the rock *** relationships among the mining depth, width of the plastic zone, rebound range of the roof and floor,stress concentration factor, and the induced kinetic energy are systematically explored. Furthermore, a rock burst risk evaluation method is proposed. The findings indicate that the energy evolution of the rock mass can be categorized into four stages: energy accumulation due to in-situ stress, energy accumulation resulting from coal compression, energy dissipation through coal plastic deformation, and energy consumption due to coal failure. The energy release from the rock mass is influenced by several factors,including mining depth, stress concentration factor, the width of the plastic zone, and the rebound range of the roof and floor. Within the plastic zone of coal, the energy released per unit volume of coal and the induced kinetic energy exhibit a nonlinear increase with mining depth and stress concentration factor,while they decrease linearly as the width of the plastic zone increases. Similarly, the driving energy per unit volume of the roof and floor shows a nonlinear increase with mining depth and stress concentration factor, a linear increase with the rebound range of the roof and floor, and a linear decrease with the width of the plastic zone. A rock burst risk evaluation method is developed based on the kinetic energy model. Field observations demonstrate that this method aligns with the drilling cuttings rock burst risk assessment method, thereby confirming its validity.

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Quantitative evaluation modeling of mobile Ad Hoc networkcommunication service availability under failure|

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International Journal of Modeling, Simulation, and Scientific Computing 2020年第6期11卷 250-267页

作者： Yanfang Fu Yichang Su Zan Wang Dengdeng Guo Fei Dai Lianjiong Zhong Jianing Wei Xi’an Technological University State and Provincial Joint Engineering Lab.of Advanced Network Monitoring and Control Xi’an 710021P.R.China Beijing Electromechanical Engineering Institute Beijing 100074 P.R.China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing 100074 P.R.China

The availability of network communication services is an important evaluation standard to measure the ability of the network to meet the user’s business *** current related research mostly focuses on the evaluation of network reliability,which cannot reflect the logical relationship between failure/maintenance and network performance *** Ad Hoc Network is a multi-hop,centerless and energy-constrained distributed *** to the dynamic change of communication environment and the instability of wireless link,Ad Hoc Network is facing great challenges in service avail*** this thesis,a fault-based quantitative evaluation model of traffic availability in Ad Hoc networks is *** studying the multi-state Markov fault model of communication networks and the performance analysis of delay index based on CSMA\CA protocol,the quantitative evaluation of traffic availability in Ad Hoc networks is *** the availability of tactical unit network under different typical network configuration conditions is analyzed through experiments.

关键词： Network reliability service availability fault model quantitative evaluation

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Magnetic exchange interaction between unpaired π-and d-electrons in nanographene-metal coordination complexes

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National science Review 2025年第04期 260-267页

作者： Deng-Yuan Li Yuqiang Zheng Ricardo Ortiz Bing-Xin Wang Yashi Jiang Bingkai Yuan Xin-Yu Zhang Can Li Liang Liu Xiaoxue Liu Dandan Guan Yaoyi Li Hao Zheng Canhua Liu Jinfeng Jia Thomas Frederiksen Pei-Nian Liu Shiyong Wang Key Laboratory of Natural Medicines Department of Medicinal ChemistryChina Pharmaceutical University Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education) TD Lee Institute Shenyang National Laboratory for Materials ScienceSchool of Physics and Astronomy Shanghai Jiao Tong University Donostia International Physics Center (DIPC) Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint Research Center Frontiers Science Center for Materiobiology and Dynamic ChemistryState Key Laboratory of Chemical Engineering School of Chemistry and Molecular Engineering East China University of Science & Technology Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences (CAS) Hefei National Laboratory Ikerbasque Basque Foundation for Science

The combination of open-shell nanographenes(NGs) and magnetic transition metals holds great promise for generating various new quantum phases applicable in spintronics and quantum information ***,a crucial aspect in accomplishing this is to comprehend the magnetic exchange interactions between unpaired π-and d-electrons,a topic that has been seldom *** this study,we focus on magnetic π-d exchange interactions between open-shell NGs and a magnetic coordination center of Fe or Co by employing scanning tunneling microscopy and *** synthesize two sets of NG-metal coordination complexes on a Au(111) substrate,secured by coordination bonds of carboxyl acid-Fe(Co).Through analysis of the excitation spectra,we observe a characteristic exchange coupling of 9 meV(5 meV) between the unpaired π-electron and the Fe(Co) d-shell *** experimental findings are qualitatively in agreement with multiconfigurational quantum chemistry *** work provides evidence that a substantial magnetic exchange coupling can be achieved and engineered in metal-organic coordination systems,paving the way for designing and customizing extended radical metal-organic frameworks with precisely tailored magnetic properties.

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Transient Response of High Dimensional Nonlinear dynamic System for a Rotating Cantilever Twisted Plate

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Advances in Applied Mathematics and Mechanics 2020年第6期12卷 1542-1564页

作者： Yuxin Hao Xiaojun Gu Wei Zhang Jie Chen College of Mechanical Engineering&Beijing Key Laboratory of Electromechanical System Measurement and Control Beijing Information Science and Technology UniversityBeijing 100192China College of Mechanical Engineering Beijing University of TechnologyBeijing 100124China Architecture and Civil Engineering Research Center Shenzhen Research InstituteCity University of Hong KongShenzhenGuangdong 518055China

dynamic transient responses of rotating twisted plate under the air-blast loading and step loading respectively considering the geometric nonlinear relationships are investigated using classical shallow shell *** applying energy principle,a novel high dimensional nonlinear dynamic system of the rotating cantilever twisted plate is derived for the first *** use of variable mode functions by polynomial functions according to the twist angles and geometric of the plate makes it more accurate to describe the dynamic system than that using the classic cantilever beam functions and the free-free beam *** comparison researches are carried out between the present results and other literatures to validate present model,formulation and computer *** of motion describing the transient high dimensional nonlinear dynamic response are reduced to a four degree of freedom dynamic system which expressed by out-plane *** effects of twisted angle,stagger angle,rotation speed,load intensity and viscous damping on nonlinear dynamic transient responses of the twisted plate have been ***’s important to note that although the homogeneous and isotropic material is applied here,it might be helpful for laminated composite,functionally graded material as long as the equivalent material parameters are obtained.

关键词： Cantilever twisted plate rotating blast loading transient response high dimensional nonlinear dynamics

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Enhanced carbonate weathering and CO2 release in a typical karst watershed (Southwest China): Evidence from hydrochemical and multi-isotopic data

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science of the Total Environment 2024年 957卷 177372页

作者： Liu, Lei Lan, Jiacheng Ren, Kun Huang, Mingzhi Mao, Ruitao Zhang, Xianwen Yue, Kunqian School of Karst Science / State Engineering Technology Institute for Karst Desertiffcation control Guizhou Normal University Guiyang550001 China Institute of Karst Geology Chinese Academy of Geological Sciences Key Laboratory of Karst Dynamics Ministry of Natural Resources & Guangxi Guilin541004 China International Research Centre on Karst under the Auspices of UNESCO National Center for International Research on Karst Dynamic System and Global Change Guilin541004 China Pingguo Guangxi Karst Ecosystem National Observation and Research Station Pingguo531406 China

Carbon sinks formed by carbonate weathering are a major component of the carbon sink deficit and play a significant role in the carbon cycle. However, exogenous acids (HNO3 and H2SO4) are also involved in carbonate weathering, complicating the overestimation of the formation of carbon sinks and fluxes. In this study, we analyzed the Hongjiadu karst underground river basin in Guizhou using isotopes (δ13C-DIC, δ34S-SO4, δ18O-SO4, δ18O-H2O, and δ2H-H2O) and hydrochemical methods to investigate carbon cycling characteristics and its influencing factors, and quantitatively evaluate the effects of HNO3 + H2SO4 on CO2 sink fluxes in the basin. The following results were obtained: (1) The nitrate in the watershed mainly comes from fertilizers, and the sulfate mainly comes from local coal seams. (2) The relationship between isotopes (δ13C-DIC, δ34S-SO4, δ18O-SO4, δ18O-H2O, and δ2H-H2O) and hydrochemicals (Ca2+, Mg2+, NO3–, HCO3–, and SO42–) indicates that H2CO3, HNO3, and H2SO4 are involved in carbonate rock dissolution. Most of the samples in the watershed, particularly the acid mine drainage water, were affected by acid rain and sulfide oxidation, resulting in increased δ13C-DIC values. Another portion of the springs was affected by soil CO2, resulting in decreased δ13C-DIC values. (3) Quantitative calculations showed that exogenous acids enhanced the weathering rate of carbonate rocks in groundwater by 67.24 % (dry season) and 76.31 % (wet season) while decreasing the carbon sink flux in groundwater by 55.31 % (dry season) and 66.64 % (wet season). Rainfall enhances the weathering of carbonate rocks. In the process, CO2 is released, increasing the carbon source. Our study highlights the influence of anthropogenic, natural, and hydrological changes on karst carbon sinks in mixed-pollution karst basins. This information is important for future studies on the carbonate weathering processes in karst regions. © 2024 Elsevier B.V.

关键词： Groundwater pollution

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Active Disturbance Rejection control Strategy Applied to Oxygen Excess Ratio for Proton Exchange Membrane Fuel Cells System

SSRN

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SSRN 2022年

作者： Huo, Weiwei Zhang, Ning Li, Chen Institute of Electromechanical Engineering Beijing Information Science and Technology University 12 Xiaoying East Road Qinghe Haidian District Beijing100192 China Collaborative Innovation Center of Electric Vehicles in Beijing Beijing Information Science & Technology University Beijing100192 China Key Laboratory of Modern Measurement and Control Technology Ministry of Education Beijing Information Science and Technology University Beijing100192 China Research Institute of Highway Ministry of Transport No. 8 Xitucheng Road Haidian District Beijing100088 China

Air inlet flow control is critical for performance of Proton Exchange Mambrane Fuel Cells (PEMFC). An essential gauge for air input flow is the oxygen excess ratio (OER). However, accurate controlling for OER is a huge challenge because of the erroneous modeling, imprecise parameter values, and disturbances. An Active Disturbance Rejection control (ADRC) approach is suggested in this research as a means of resolving the issue of fuel cells' internal and exterior interference. Firstly, the total disturbance is obtained using an extended state observer. Secondly, the total disturbance is compensated before the control action to determine the control quantity for air supply, which is further controlled by modifying the air compressor's voltage. The performance comparison between the suggested approach and PID and fuzzy PID control shows that the proposed technique can achieve a higher reliability for managing the mechanical faults of the air compressor. In addition, the root mean square error (RMSE) of control time and overshoot is smaller. © 2022, The Authors. All rights reserved.

关键词： Proton exchange membrane fuel cells (PEMFC)

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