检索结果-内蒙古大学图书馆

Distributed formation-aggregation control algorithm for a cluster of quadrotors

Journal of the Franklin Institute 2023年第3期360卷 1560-1581页

作者： Sun, Yongbin Li, Jiayi Wang, Zixuan He, Xiuyu Fu, Qiang Zou, Yao School of Automation Science and Electrical Engineering Beihang University Beijing100191 China School of Intelligence Science and Technology University of Science and Technology Beijing Beijing100083 China Key Laboratory of Perception and Control of Intelligent Bionic Unmanned Systems Ministry of Education University of Science and Technology Beijing Beijing100083 China

This paper focuses on the solution to a formation-aggregation problem concerned with a cluster of quadrotors. In particular, all the quadrotors are steered towards a target region while reaching an expected formation configuration. However, only a subset of quadrotors, treated as leaders, have access to the projections onto the target region;and in the meantime, each quadrotor just exchanges information with its neighbors. It is assumed that the quadrotors without the knowledge of the target region, treated as followers, are within the convex hull of the leaders in the expected configuration. A distributed formation-aggregation control algorithm is proposed under the hierarchical framework. To be specific, resorting to an auxiliary dynamic system with a distributed idea, a command force is first synthesized in the position loop for the concerned formation-aggregation objective. Next, an applied thrust and a command attitude are extracted from the synthesized command force. Finally, an applied torque is synthesized in the attitude loop such that the attitude tracking to the command one is realized. In terms of the Lyapunov theory, it is shown that the leaders are capable of guiding the overall quadrotor cluster into the target region in the expected configuration. Simulations are carried out to validate the theoretical results. © 2022 The Franklin Institute

关键词： Computer networks

来源：评论

学校读者我要写书评

暂无评论

Broadband and High-Power Sub-terahertz Gyro-TWTs and Ultrashort Electromagnetic Pulse Generation 5th

Broadband and High-Power Sub-terahertz Gyro-TWTs and Ultrash...

引用

5th China and International Young Scientist Terahertz Conference, YTHZ 2024

作者： Liu, Guo Jiang, Wei Yao, Yelei Wang, Weijie Cao, Yingjian Wang, Yu Wu, Zewei Pu, Youlei Wang, Jianxun Luo, Yong University of Electronic Science and Technology of China Chengdu611731 China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing100089 China

ISBN: (纸本)9789819739127

In this paper, a short demonstration about the recent progress of our high-power broadband gyrotron travelling wave tube (gyro-TWT) amplifiers in the sub-terahertz band (W and G-band) are respectively reported. Hot test of the W- and G-band gyro-TWTs had respectively achieved a pulsed/averaged output power of over 120 kW/20 kW and 35 kW/2.1 kW within a 10 GHz bandwidth. Based on the fabricated sub-terahertz gyro-TWTs, a scheme to generate high power, ultrashort electromagnetic pulses based on the chirped signal compressor is also presented, which had been verified in the micro- and millimeter wave band. The presented sub-terahertz high-power sources and ultrashort pulses have potential applications in the high-resolution imaging radar, deep space communication, bio-medicine, material modification and catalysis, etc. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Gyroscopes

来源：评论

学校读者我要写书评

暂无评论

Modeling and Experimental Study of an Open Two-Phase Loop Driven by Osmotic Pressure and Capillary Force

引用

Frontiers in Heat and Mass Transfer 2025年第1期23卷 55-70页

作者： Hanli Bi Zheng Peng Chenpeng Liu Zhichao Jia Guoguang Li Yuandong Guo Hongxing Zhang Jianyin Miao National Key Laboratory of SpacecraftThermal Control Beijing Institute of Spacecraft System EngineeringChina Academy of Space TechnologyBeijing100094China School of Aeronautical Science and Engineering Beihang UniversityBeijing100083China School of Energy and Environment Engineering University of Science and Technology BeijingBeijing100083China

As space technology advances,thermal control systems must effectively collect and dissipate heat from distributed,multi-source *** heat pipe is a highly reliable two-phase heat transfer component,but it has several limitations when addressing multi-source heat *** by the transport and heat dissipation system of plants,large trees achieve stable and efficient liquid supply under the influence of two driving forces:capillary force during transpiration in the leaves(pull)and root pressure generated by osmotic pressure in the roots(push).The root pressure provides an effective liquid supply with a driving force exceeding 2 MPa,far greater than the driving force in conventional capillary-pumped two-phase *** has shown that osmotic heat pipes offer a powerful driving force,and combining osmotic pressure with capillary force has significant ***,this paper designs a multi-evaporator,dual-drive two-phase loop,using both osmotic pressure and capillary force to solve the multi-source heat dissipation ***,a transmembrane water flux model for the osmotic pressure-driven device was established to predict the maximum heat transfer capacity of the dual-drive two-phase ***,an experimental setup for a multi-evaporator“osmotic pressure+capillary force”dual-drive two-phase loop was constructed,capable of transferring at least 235 W of power under a reverse gravity condition of 20 *** study also analyzed the effects of reverse gravity height,heat load distribution among the three evaporators,startup sequence,and varying branch resistances on the performance of the dual-drive two-phase loop.

关键词： Multi-heat sources osmotic pressure two-phase loop dual-drive loop heat pipe

来源：评论

学校读者我要写书评

暂无评论

System identification under saturated precise or set-valued measurements

引用

science China(Information sciences) 2023年第1期66卷 224-243页

作者： Yanlong ZHAO Hang ZHANG Ting WANG Guolian KANG Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences Institute of Artificial Intelligence University of Science and Technology Beijing Department of Biostatistics St.Jude Children's Research Hospital

This paper considers the system identification problem based on saturated precise or set-valued measurements, which is widely used in various fields and has essential difficulties. Since existing methodologies cannot make full use of the mixed data, this paper is aiming to fill the gap and build a unified framework in dealing with such problems rigorously and comprehensively. New algorithms are introduced and their properties are established. Most significantly, the Cramécr-Rao(CR) lower bound based on the measurements is established, which consists of two parts with respect to the precise data and set-valued data, respectively. This prompts the idea of designing an estimation algorithm by grouping and combining the estimations under two classifications of data. As a result, a CR lower bound-based algorithm(CRBA) is constructed. The convergence properties are theoretically analyzed in terms of consistency and asymptotic efficiency under periodic inputs. For general inputs, an algorithm based on the CRBA that combines the expectation maximization(EM) algorithm for set-valued subsystems and the gradient descent algorithm for precise subsystems is proposed. Numerical simulations validate the superiority of the proposed algorithms.

关键词： system identification Cramér-Rao lower bound truncated data precise measurement set-valued measurement

来源：评论

学校读者我要写书评

暂无评论

Size Effect on the Radiation Stability Silicon Dioxide Sphere Particles

引用

Journal of Harbin Institute of technology(New Series) 2024年第4期31卷 1-12页

作者： Vitaly Neshchimenko Chundong Li Mikhail Mikhailov Jinpeng Lv Laboratory of Radiation Stability Evaluation of Thermal Control Coatings Amur State UniversityBlagoveshchensk 675000Russia Science and Technology on Material Performance Evaluating in Space Environment Laboratory Harbin Institute of TechnologyHarbin 150001China Radiation and Space Materials Laboratory Tomsk State University of Control Systems and Radio-ElectronicsTomsk 634050Russia Department of Material Science and Technology Nanjing University of Aeronautics&AstronauticsNanjing 210016China

The effect of protons(E = 100 keV,F = 5×10^(15) cm^(-2)) exposure on the diffuse reflectance spectra of the SiO_(2 )with different size particles in wavelength range from 250 to 2500 nm have been *** were nanosphere,submicrosphere,microsphere and submacrosphere,as well as solid micro-and *** synthesis of the particles was carried out by the formation of silica shells and dissolution of the polystyrene core *** surface morphology,surface area and crystal structure of the particles have been *** evaluating the changes of the solar absorptance,it was found that the radiation stability of the micro-and submacro-hollow particles is higher than that of the other nanostructured particles,except for solid *** low radiation stability of the hollow microparticles is due to the large void inside the hollow particles where radiation defects are not formed.

关键词： silicon dioxide hollow particles spectral reflectance irradiation

来源：评论

学校读者我要写书评

暂无评论

The Caching and Pricing Strategy for Information-Centric Networking with Advertisers’Participation

引用

China Communications 2024年第3期21卷 283-295页

作者： Zheng Quan Yan Wenliang Wu Rong Tan Xiaobin Yang Jian Yuan Liu Xu Zhenghuan Laboratory for Future Networks Department of AutomationUniversity of Science and Technology of ChinaHefei 230026China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei 230088China Institute of Advanced Technology University of Science and Technology of ChinaHefei 230088China Suzhou Nuclear Power Research Institute Suzhou 215004China National Engineering Laboratory for Public Safety Risk Perception and Control by Big Data(NEL-PSRPC) China Academy of Electronics and Information Technology of CETCBeijing 100041China

As users’access to the network has evolved into the acquisition of mass contents instead of IP addresses,the IP network architecture based on end-to-end communication cannot meet users’***,the Information-Centric Networking(ICN)came into *** a technical point of view,ICN is a promising future network *** and customizing a reasonable pricing mechanism plays a positive role in promoting the deployment of *** current research on ICN pricing mechanism is focused on paid ***,we study an ICN pricing model for free content,which uses game theory based on Nash equilibrium to *** this work,advertisers are considered,and an advertiser model is established to describe the economic interaction between advertisers and ICN *** solution can formulate the best pricing strategy for all ICN entities and maximize the benefits of each *** extensive analysis and numerical results show that the proposed pricing framework is significantly better than existing solutions when it comes to free content.

关键词： advertisers cache free content Information-Centric Networking pricing strategy

来源：评论

学校读者我要写书评

暂无评论

Multi-spacecraft Fly-Around control Method for Mixed Cooperative-Competitive Scenarios

Multi-Spacecraft Fly-Around Control Method for Mixed Coopera...

引用

2022 Chinese Automation Congress, CAC 2022

作者： Wang, Yingjie Yuan, Li Huang, Huang Tang, Liang Geng, Yuanzhuo Beijing Institute of Control Engineering Beijing China China Academy of Space Technology Science Technology on Space Intelligent Control Laboratory Beijing China Beijing Institute of Control Engineering Science Technology on Space Intelligent Control Laboratory Beijing China

ISBN: (纸本)9781665465335

Fly-around is important in many tasks such as on-orbit servicing. When a target exhibits game-playing behavior such as orbit maneuver for evasion, predesigned fly-around formation and control strategies can't deal with the situation well enough. For mixed cooperative-competitive scenarios, this paper proposes a multi-spacecraft fly-around control method based on deep reinforcement learning. In order to motivate cooperative behavior among chasers, this paper designs structured reward function combining individual reward with collective reward for chasers. Meanwhile, in order to motivate competitive behavior of chasers, this paper designs appropriate reward function for target as practice partner. Self-play training mechanics using PPO algorithm is developed to train the chasers and the target simultaneously. Experiments show chasers can maintain appropriate formation around the target and adjust their formation to adjust to the changes of sunlight direction and unknown target behaviors. © 2022 IEEE.

关键词： Deep learning

来源：评论

学校读者我要写书评

暂无评论

A Navigation and control Framework of Quadrupedal Robot for Autonomous Exploration in Cave Environments 16th

A Navigation and Control Framework of Quadrupedal Robot for ...

引用

16th International Conference on Intelligent Robotics and Applications, ICIRA 2023

作者： Hu, Yong Jiang, Lisong Kang, Ke Cao, Dandan Zhou, Zhongda Liu, Junfeng Wang, Yong Li, Maodeng Hu, Haidong National Key Laboratory of Science and Technology On Space Intelligent Control Beijing Institute of Control Engineering Beijing100190 China China Academy of Space Technology Hangzhou Institute Hangzhou310001 China

ISBN: (纸本)9789819964796

This article introduces XiaoTian, a quadrupedal robot with high mobility, dynamic motion skills, and autonomous ability. The robot uses backdriveable joint actuators with high force density, and robustness to impacts during trotting. Considering the specific application environment, we design the overall navigation and control framework of the robot, including the motion controlling, mapping, and planning methods. The experiment proved that XiaoTian can perform walking gaits, dynamically trot on the uneven ground and achieve autonomous exploration in the dark cave environments. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023.

关键词： Navigation

来源：评论

学校读者我要写书评

暂无评论

Decomposing Visual and Semantic Correlations for Both Fully Supervised and Few-Shot Image Classification

IEEE Transactions on Artificial Intelligence

引用

IEEE Transactions on Artificial intelligence 2024年第4期5卷 1658-1668页

作者： Zhang, Chunjie Zheng, Xiaolong Beijing Jiaotong University Institute of Information Science Beijing100044 China Beijing Jiaotong University Beijing Key Laboratory of Advanced Information Science and Network Technology Beijing100044 China University of Chinese Academy of Sciences State Key Laboratory of Multimodal Artificial Intelligence Systems The State of Key Laboratory of Management and Control for Complex System Institute of Automation Chinese Academy of Sciences School of Artificial Intelligence Beijing100190 China

Most image classification methods are designed to either boost the classification accuracies with abundant supervision, or cope with the shortage of supervision information. This is often achieved by using the visual and semantic information of other sources. However, these methods use the visual and semantic information within the same class independently, leaving their intrinsic correlations unconsidered. Objects and disturbing components as well as noise exist on the same image. Besides, semantic representations also contain noisy information. To solve the problems mentioned above, we propose a novel method for both fully supervised image classification and few-shot image classification by decomposing visual and semantic correlations. We jointly explore the intrinsic correlations of visual and semantic information of images within the same class. For each class, we decompose its visual and semantic correlations using low-rank and sparse constraint respectively. The decomposed low-rank parts character the intrinsic correlations of images can be used in a linear transformation way. Using the decomposed parts of each class, Classification can be achieved by reconstruction error minimization. We conduct experiments on several datasets for both fully supervised image classification and few-shot image classification. Experimental results well show the effectiveness of the proposed method. © 2020 IEEE.

关键词： Semantics

来源：评论

学校读者我要写书评

暂无评论

WPIA:accelerating DNN warm-up in Web browsers by precompiling WebGL programs

引用

Frontiers of Computer science 2024年第6期18卷 281-283页

作者： Deyu TIAN Yun MA Yudong HAN Qi YANG Haochen YANG Gang HUANG Key Laboratory of High Confidence Software Technologies(Peking University) Ministry of EducationSchool of Computer SciencePeking UniversityBeijing 100871China Institute for Artificial Intelligence Peking UniversityBeijing 100871China National Key Laboratory of Data Space Technology and System Beijing 100195China

1 *** the advent of artificial intelligence,it is becoming increasingly common to leverage deep learning technologies to provide intelligent services in Web apps[1].Compared with traditional approaches where deep neural network(DNN)runs at cloud servers,DNN inference in Web browsers avoids serverconnections,boostingtheresponsivenesssand enhancing user privacy of Web apps[2].Typically,GPU acceleration is required during DNN inference,especially on enddevices.

关键词： Web browser WebGL

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：