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An Intelligent Ellipsoid Calibration Method Based on the Grey Wolf Algorithm for Magnetic Compass

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Journal of Bionic Engineering 2021年第2期18卷 453-461页

作者： xusheng lei Xiaoyu Zhang Yankun Hao School of the Instrumentation Science and Opto-Electronic Engineering Beihang UniversityBeijing 100191China

With the measurement of the Earth’s magnetic field,magnetic compass can provide high frequency heading ***,it suffers from local magnetic *** intelligent ellipsoid calibration method based on the grey wolf is proposed to generate optimal parameters for magnetic compass to generate high performance heading *** the analysis of the projection relationship among the navigation coordinate frame,the body frame and the local horizontal frame,the heading ellipsoid equation is ***,an improved grey wolf algorithm is proposed to find optimization solution in a large solution *** the improvement of the convergence factor and the evolutionary mechanism,the improved grey wolf algorithm can generate optimized solution for heading ellipsoid *** effectiveness of the proposed method has been verified by a series of vehicle and flight *** experimental results show that the proposed method can eliminate errors caused by sensor defects,hard-iron interference,and soft-iron interference *** heading error generated by the magnetic compass is less than 0.2162 degree in real flight tests.

关键词： magnetic compass ellipsoid parameters grey wolf algorithm error model

In-situ observation and finite element analysis of fretting fatigue crack propagation behavior in 1045 steel

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Chinese Journal of Aeronautics 2021年第11期34卷 131-139页

作者： Qinan HAN xusheng lei Yue SU Shaoshi RUI Xianfeng MA Haitao CUI Huiji SHI Aero-engine Thermal Environment and Structure Key Laboratory of Ministry of Industry and Information Technology College of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China AML Department of Engineering MechanicsTsinghua UniversityBeijing 100084China AMPTL Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China

In this paper fretting fatigue crack behavior in 1045 steel is studied by in-situ observation and finite element ***-situ fretting fatigue experiments are conducted to capture real-time fretting fatigue crack formation and propagation *** fretting fatigue tests under different load conditions are carried out,then the lifetime and fracture surface are *** crack propagation rates under different loading conditions are measured by in-situ *** in-situ observation,crack initiation location and direction are *** element model is used to calculate J-integral which then is applied to fitting with experimental crack growth rate,and establishing crack growth rate *** fitted S-N curve,it turns out that smaller load ratio leads to higher *** initiates slightly below the point equivalent to line contact of the contact surface in different test conditions,and crack direction shows no obvious relationship with load *** established crack growth rate model well agrees with the test results.

关键词： Crack growth rate Fretting fatigue In-situ observation J-integral 1045 steel

A Linear Domain System Identification for Small Unmanned Aerial Rotorcraft Based on Adaptive Genetic Algorithm

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Journal of Bionic Engineering 2010年第2期7卷 142-149页

作者： xusheng lei,Yuhu Du School of the Instrumentation Science and Opto-Electronic Engineering,Beihang University,Beijing 100191,P.R.China School of the Instrumentation Science and Opto-Electronic Engineering Beihang University Beijing P. R. China

This paper proposes a new adaptive linear domain system identification method for small unmanned aerial *** the flash memory integrated into the micro guide navigation control module, system records the data sequences of flighttests as inputs (control signals for servos) and outputs (aircraft’s attitude and velocity information).After data preprocessing, thesystem constructs the horizontal and vertical dynamic model for the small unmanned aerial rotorcraft using adaptive *** identified model is verified by a series of simulations and *** between flight data and the one-stepprediction data obtained from the identification model shows that the dynamic model has a good estimation for real unmannedaerial rotorcraft *** on the proposed dynamic model, the small unmanned aerial rotorcraft can perform hovering,turning, and straight flight tasks in real flight tests.

关键词： small unmanned aerial rotorcraft dynamic space model model identification adaptive genetic algorithm

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小型无人飞行器风场扰动自适应控制方法

航空学报 2010年第6期31卷 1171-1176页

作者：雷旭升陶冶北京航空航天大学仪器科学与光电工程学院北京100191

针对小型无人飞行器在执行任务时传感器测量精度低、受风场扰动影响大的问题,提出了一种利用矢量域与滑模控制相结合的复合控制方式,有效地实现了对小型无人飞行器的轨迹与航向的自适应跟踪。将复杂航迹分解为直线段与圆弧段分别构建矢... 详细信息

针对小型无人飞行器在执行任务时传感器测量精度低、受风场扰动影响大的问题,提出了一种利用矢量域与滑模控制相结合的复合控制方式,有效地实现了对小型无人飞行器的轨迹与航向的自适应跟踪。将复杂航迹分解为直线段与圆弧段分别构建矢量域,从而确定基于位置误差的航迹信息,并通过机载传感器获得状态和位置信息,利用滑模控制方法抑制风场扰动对小型无人飞行器的影响。试验结果表明,本文提出的控制算法能够保证阵风干扰情况下小型无人飞行器的航迹控制精度,同时具有良好的动态响应。

关键词：小型无人飞行器风场扰动航迹跟踪矢量域滑模控制

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基于ESO的无人直升机高精度姿态控制

机器人 2020年第4期42卷 406-415,426页

作者：范大东雷旭升北京航空航天大学仪器科学与光电工程学院北京100191

针对小型无人直升机存在模型参数不确定性、电磁干扰影响的问题,设计了一种基于ESO(扩张状态观测器)的高精度姿态控制方法.直升机姿态通道中的不确定部分及外界复合扰动被视为总扰动,通过ESO进行实时估计,结合状态反馈控制器实现扰动消... 详细信息

针对小型无人直升机存在模型参数不确定性、电磁干扰影响的问题,设计了一种基于ESO(扩张状态观测器)的高精度姿态控制方法.直升机姿态通道中的不确定部分及外界复合扰动被视为总扰动,通过ESO进行实时估计,结合状态反馈控制器实现扰动消除.试验结果表明,在0.1 s内姿态角可从0°快速跟踪到5°且无超调.最后将设计的控制器应用于研制的高精度无人驾驶系统,实现系统参数变动等条件下直升机的全自主定点悬停和航迹飞行.

关键词：无人直升机飞行控制扩张状态观测器(ESO)

Optimal replication strategy for mitigating burst traffic in information-centric satellite networks: a focus on remote sensing image transmission

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Frontiers of Information Technology & Electronic Engineering 2024年第6期25卷 791-808页

作者： Ziyang XING Xiaoqiang DI Hui QI Jing CHEN Jinhui CAO Jinyao LIU xusheng LI Zichu ZHANG Yuchen ZHU lei CHEN Kai HUANG Xinghan HUO Jilin Key Laboratory of Network and Information Security Changchun 130022China School of Computer Science and Technology Changchun University of Science and TechnologyChangchun 130022China Information Center Changchun University of Science and TechnologyChangchun 130022China

Information-centric satellite networks play a crucial role in remote sensing applications,particularly in the transmission of remote sensing ***,the occurrence of burst traffic poses significant challenges in meeting the increased bandwidth *** content delivery networks are ill-equipped to handle such bursts due to their pre-deployed *** this paper,we propose an optimal replication strategy for mitigating burst traffic in information-centric satellite networks,specifically focusing on the transmission of remote sensing *** strategy involves selecting the most optimal replication delivery satellite node when multiple users subscribe to the same remote sensing content within a short time,effectively reducing network transmission data and preventing throughput degradation caused by burst traffic *** formulate the content delivery process as a multi-objective optimization problem and apply Markov decision processes to determine the optimal value for burst traffic *** address these challenges,we leverage federated reinforcement learning ***,we use bloom filters with subdivision and data identification methods to enable rapid retrieval and encoding of remote sensing *** software-based simulations using a low Earth orbit satellite constellation,we validate the effectiveness of our proposed strategy,achieving a significant 17%reduction in the average delivery *** paper offers valuable insights into efficient content delivery in satellite networks,specifically targeting the transmission of remote sensing images,and presents a promising approach to mitigate burst traffic challenges in information-centric environments.

关键词： Information-centric satellite network Burst traffic Content delivery Federated reinforcement learning Mixed-integer linear programming model Bloom filter Dynamic network

基于长机—僚机模式的无人机编队方法及飞行实验研究

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机器人 2010年第4期32卷 505-509页

作者：洪晔缪存孝雷旭升北京航空航天大学仪器科学与光电工程学院北京100191

针对目前无人机编队方法无法在实际飞行实验中应用的问题,设计了基于长机—僚机跟踪模式的双机协同编队算法,以双机的空间距离为控制对象,将所有的控制指令转化为速度、航向和高度指令.为实现实际编队飞行,基于实验室自行研发的小型无人... 详细信息

针对目前无人机编队方法无法在实际飞行实验中应用的问题,设计了基于长机—僚机跟踪模式的双机协同编队算法,以双机的空间距离为控制对象,将所有的控制指令转化为速度、航向和高度指令.为实现实际编队飞行,基于实验室自行研发的小型无人机,建立双串口地面控制系统硬件平台,重点解决了双串口的实现及双机数据同步问题.地面跑车实验和实际飞行实验表明:该地面控制系统可以很好地实现双机的数据通信,控制指令实时上传准确,协同算法正确有效.

关键词：小型无人机双串口地面控制系统编队飞行

Synthesis and anti-HIV activities of phorbol derivatives

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Chinese Journal of Natural Medicines 2024年第2期22卷 146-160页

作者： HUANG Xiaolei TANG Chengrun HUANG xusheng YANG Yun LI Qirun MA Mengdi ZHAO lei YANG Liumeng CUI Yadong ZHANG Zhenqing ZHENG Yongtang ZHANG Jian College of Pharmaceutical Science Soochow UniversitySuzhou 215123China Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences/Key Laboratory of Bioactive Peptides of Yunnan Province Kunming Institute of ZoologyChinese Academy of SciencesKunming 650223China Kunming College of Life Science University of Chinese Academy of SciencesKunmingYunnan 650204China

In this study,37 derivatives of phorbol esters were synthesized and their anti-HIV-1 activities evaluated,building upon our previous synthesis of 51 phorbol derivatives.12-Para-electron-acceptor-trans-cinnamoyl-13-decanoyl phorbol derivatives stood out,demonstrating remarkable anti-HIV-1 activities and inhibitory effects on syncytia *** derivatives exhibited a higher safety index compared with the positive control *** them,12-(trans-4-fluorocinnamoyl)-13-decanoyl phorbol,designated as compound 3c,exhibited the most potent anti-HIV-1 activity(EC_(50)2.9 nmol·L^(−1),CC50/EC_(50)11117.24)and significantly inhibited the formation of syncytium(EC_(50)7.0 nmol·L^(−1),CC50/EC_(50)4891.43).Moreover,compound 3c is hypothesized to act both as an HIV-1 entry inhibitor and as an HIV-1 reverse transcriptase *** titration calorimetry and molecular docking studies indicated that compound 3c may also function as a natural activator of protein kinase C(PKC).Therefore,compound 3c emerges as a potential candidate for developing new anti-HIV drugs.

关键词： Phorbol esters Anti-HIV-1 activity Syncytia formation 12-(Trans-4-fluorocinnamoyl)-13-decanoyl phorbol Safety index HIV-1 entry inhibitor HIV-1 reverse transcriptase inhibitor PKC activator

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基于智能体的仿人机器人分层控制系统

高技术通讯 2007年第6期17卷 586-590页

作者：陈健雷旭升苏剑波上海交通大学自动化系上海200240

提出了基于智能体的仿人机器人分层控制思想,构建了由主控层、通信层和执行层三部分构成的仿人机器人分层控制系统。机器人执行层分为多个独立的智能体,每个智能体具有控制器、必要的传感器和关节驱动器,机器人的伺服控制由这些智能体... 详细信息

提出了基于智能体的仿人机器人分层控制思想,构建了由主控层、通信层和执行层三部分构成的仿人机器人分层控制系统。机器人执行层分为多个独立的智能体,每个智能体具有控制器、必要的传感器和关节驱动器,机器人的伺服控制由这些智能体实现。这样整个系统能够充分发挥智能体的反应性、自治性、预动性和社会性等特性,不仅可以直接处理原始传感器数据,而且可以单独或通过多个智能体之间的协调直接对机器人的一些异常情况进行处理,如机器人遇到障碍物、机器人连杆臂碰撞等,可以提高仿人机器人的稳定性和实时性。实验结果表明,相比传统的分布式控制系统,采用基于智能体的分层控制系统可以提高机器人的稳定性和实时性。

关键词：仿人机器人分层控制系统智能体实时性