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Adaptive level of autonomy for human-UAVs collaborative surveillance using situated fuzzy cognitive maps

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Chinese Journal of Aeronautics 2020年第11期33卷 2835-2850页

作者： Zhe ZHAO yifeng niu Lincheng SHEN College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China

Collaborating with a squad of Unmanned Aerial Vehicles(UAVs)is challenging for a human operator in a cooperative surveillance task.In this paper,we propose a cognitive model that can dynamically adjust the Levels of Autonomy(LOA)of the human-UAVs team according to the changes in task complexity and human cognitive states.Specifically,we use the Situated Fuzzy Cognitive Map(Si FCM)to model the relations among tasks,situations,human states and LOA.A recurrent structure has been used to learn the strategy of adjusting the LOA,while the collaboration task is separated into a perception routine and a control routine.Experiment results have shown that the workload of the human operator is well balanced with the task efficiency.

关键词： Adaptive LOA Cognitive Model Human-UAVs collaboration Situated Fuzzy Cognitive Map(SiFCM) Time series learning

Consensus disturbance rejection control of directed multi-agent networks with extended state observer

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Chinese Journal of Aeronautics 2020年第5期33卷 1486-1493页

作者： Shaopan GUO Zhongkui LI yifeng niu Lizhen WU State Key Laboratory for Turbulence Complex System Department of Mechanics and Aerospace EngineeringPeking UniversityBeijing 100871China College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China

This paper investigates the consensus disturbance rejection problem among multiple high-order agents with directed graphs.Based on disturbance observers,distributed consensus disturbance rejection protocols are constructed in leaderless and leader-follower consensus setups.Different from the previous related papers,the consensus protocols in this paper are developed in a fully distributed fashion,relying on only the state information of each agent and its neighbors.Sufficient conditions are provided to guarantee that the asymptotic stability of high-order multi-agent systems can be reached with matched disturbances.

关键词： Adaptive control Consensus control Distributed control Disturbance rejection Multi-agent systems

UAV low-altitude obstacle detection based on the fusion of LiDAR and camera

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Autonomous Intelligent Systems 2021年第1期1卷 182-191页

作者： Zhaowei Ma Wenchen Yao yifeng niu Bosen Lin Tianqing Liu College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410000China

In this paper,aiming at the flying scene of the small unmanned aerial vehicle(UAV)in the low-altitude suburban environment,we choose the sensor configuration scheme of LiDAR and visible light camera,and design the static and dynamic obstacle detection algorithms based on sensor fusion.For static obstacles such as power lines and buildings in the low-altitude environment,the way that image-assisted verification of point clouds is used to fuse the contour information of the images and the depth information of the point clouds to obtain the location and size of static obstacles.For unknown dynamic obstacles such as rotary-wing UAVs,the IMM-UKF algorithm is designed to fuse the distance measurement information of point clouds and the high precision angle measurement information of image to achieve accurate estimation of the location and velocity of the dynamic obstacles.We build an experimental platform to verify the effectiveness of the obstacle detection algorithm in actual scenes and evaluate the relevant performance indexes.

关键词： UAV Obstacle detection Sensor fusion

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防错技术在白车身制造过程中的应用

汽车实用技术 2024年第2期49卷 139-143页

作者：梁翠牛毅峰上汽通用五菱汽车股份有限公司重庆分公司重庆401120

针对汽车产品多元化、车型柔性化的生产需求,车间现场防错种类繁多,文章通过实例介绍了机械限位防错装置、设备检测提醒、智能扫错等防错方法,降低了生产现场相似零部件错装、漏装、漏焊、位置偏移等质量缺陷,提升了白车身输出效率。同... 详细信息

针对汽车产品多元化、车型柔性化的生产需求,车间现场防错种类繁多,文章通过实例介绍了机械限位防错装置、设备检测提醒、智能扫错等防错方法,降低了生产现场相似零部件错装、漏装、漏焊、位置偏移等质量缺陷,提升了白车身输出效率。同时对生产线的防错进行归纳总结,为其他企业提供参考借鉴。

关键词：防错技术机械限位防错设备检测提醒白车身制造

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Guidance, Navigation and Control 2021年第3期1卷 115-139页

作者： Xudong Li Lizhen Wu yifeng niu Shengde Jia Bosen Lin College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410078P.R.China

In this paper,an algorithm for solving the multi-target correlation and co-location problem of aerial-ground heterogeneous system is investigated.Aiming at the multi-target correlation problem,the fusion algorithm of visual axis correlation method and improved topological similarity correlation method are adopted in view of large parallax and inconsistent scale between the aerial and ground perspectives.First,the visual axis was preprocessed by the threshold method,so that the sparse targets were initially associated.Then,the improved topological similarity method was used to further associate dense targets with the relative position characteristics between targets.The shortcoming of dense target similarity with small di®erence was optimized by the improved topological similarity method.For the problem of colocation,combined with the multi-target correlation algorithm in this paper,the triangulation positioning model was used to complete the co-location of multiple targets.In the experimental part,simulation experiments and°ight experiments were designed to verify the e®ectiveness of the algorithm.Experimental results show that the proposed algorithm can e®ectively achieve multi-target correlation positioning,and that the positioning accuracy is obviously better than other positioning methods.

关键词： Aerial-ground system multi-target correlation topological similarity method cooperative localization

Research progress on 2D ferroelectric and ferrovalley materials and their neuromorphic application

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Science China(Physics,Mechanics & Astronomy) 2023年第11期66卷 55-76页

作者： Yifan Tan Junding Zheng Xuezhong niu yifeng Zhao Ni Zhong Bobo Tian Chungang Duan Key Laboratory of Polar Materials and Devices Ministry of EducationShanghai Center of Brain-inspired Intelligent Materials and DevicesDepartment of ElectronicsEast China Normal UniversityShanghai200241China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan030006China

Two-dimensional(2D)ferroelectric and ferrovalley materials have recently received extensive attention due to their significant advantages for modern electronic devices,such as miniaturization,low-dissipation,non-volatility,and multi-functionality.More interestingly,the couplings between the ferroic orders in these materials have enriched the development of intelligent devices,especially in neuromorphic computing.In this paper,the research progress of 2D ferroelectric and ferrovalley materials is introduced and the coupling effects between them are also described.Then,we briefly introduce recent neuromorphic computing reports based on 2D ferroelectric materials and give perspectives on ferrovalley neuromorphic devices.

关键词： two-dimensional materials ferroelectric materials multiferroic coupling neuromorphic application

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从美路线图看无人系统技术体系与发展趋势

无人系统技术 2024年第2期7卷 14-27页

作者：喻煌超全世鸣牛轶峰尹栋李杰国防科技大学智能科学学院长沙410073

对无人系统技术进行了综合评述,并对其发展趋势进行了展望。首先,基于美国国防部八版无人机/无人系统路线图的规划,深入分析了互操作性、自主性、人机协同、通信、网络安全、动力与能源、载荷等主要技术方向的内涵和关键能力,绘制了各... 详细信息

对无人系统技术进行了综合评述,并对其发展趋势进行了展望。首先,基于美国国防部八版无人机/无人系统路线图的规划,深入分析了互操作性、自主性、人机协同、通信、网络安全、动力与能源、载荷等主要技术方向的内涵和关键能力,绘制了各个技术方向的发展规划脉络。随后,调研分析了美国在不同技术方向的发展现状和应用情况。最后,综合路线图分析和发展情况分析,研判了未来无人系统技术的发展趋势。综述表明,未来无人系统技术将呈现体系化、智能化、高能化三大发展趋势。所提出的从路线图规划和发展现状分析来研判无人系统技术发展的方法对厘清无人系统技术体系和发展趋势具有一定借鉴意义。

关键词：自主性互操作性人机协同通信网络安全动力与能源载荷高能化

AN IMPROVED ALGORITHM FOR SOLVING ALL D-MPS IN MULTI-STATE NETWORKS

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Journal of Systems Science and Systems Engineering 2017年第6期26卷 711-731页

作者： niu, yifeng Gao, Ziyou Sun, Huijun School of Mathematics and Information Science Henan Polytechnic University Jiaozuo China School of Traffic and Transportation Beijing Jiaotong University Beijing China

Reliability is a desirable performance indicator of many real-world systems to measure the quality level. One general method for evaluating multi-state reliability is using d-minimal paths （d-MPs）. However, being an NP-hard problem, searching for all d-MPs is a rather challenging task. This paper proposes an improved algorithm to solve the d-MP problem. To reduce the search space of d-MPs, a concept of lower capacity bound is introduced into the d-MP problem, and an effective technique is developed to fred lower capacity bounds. Meanwhile, the fast enumeration method which is a recent improvement to the traditional enunaeration method is employed to solve d-MPs. In addition, by introducing the operation of transforming undirected edges into directed edges, the proposed algorithm is applicable to solving both directed networks and undirected networks. Through numerical experiments, it is found that the proposed algorithm holds a distinct advantage over the existing methods in solving all d-MPs.

关键词： Reliability multi-state network d-minimal paths state vector

Suppression of discontinuous precipitation and strength improvement by Sc doping in Cu-6 wt%Ag alloys

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Journal of Materials Science & Technology 2023年第4期135卷 80-96页

作者： Bailing An Rongmei niu Yan Xin William LStarch Zhaolong Xiang yifeng Su Robert E.Goddard Jun Lu Theo M.Siegrist Engang Wang Ke Han Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China National High Magnetic Field Laboratory Florida State UniversityTallahasseeFL 32310USA Oak Ridge National Laboratory Oak RidgeTN 37830USA FAMU-FSU College of Engineering TallahasseeFL 32310USA

In low-Ag Cu matrix alloys,the presence of coarse discontinuous precipitates may limit strength.We demonstrated that discontinuous precipitation was suppressed,and continuous precipitation was en-hanced by the doping of Cu-6 wt%Ag with Sc.A high-volume fraction of continuous precipitates,which nucleated on{111}planes,led to a 55 MPa increase in strength,with only a slight decrease in electri-cal conductivity.The addition of Sc inhibited the nucleation of discontinuous precipitates by causing the Sc and the Ag to co-segregate onto grain boundaries,thus forming a thin intermetallic compound layer between grains.After deformation,both discontinuous and continuous precipitates were drawn into Ag fibers.The combination of deformation strain and doping caused an increase in density and a decrease in the diameter of Ag fibers,resulting in about 205 MPa increase in doped samples when the deformation strain reached 4.9.The thinner,denser Ag fibers in the doped samples also caused higher electron scatter-ing at interfaces,leading to electrical conductivity that was 11%IACS lower than in non-doped samples.For reference,100%IACS(International Annealed Copper Standard)is equivalent to 1.7241μΩcm.

关键词： Sc doping Grain boundary segregation Precipitation Strength Electrical conductivity Plastic deformation