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An approach for formation design and flight performance prediction based on aerodynamic formation unit:Energy-saving considerations

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Chinese Journal of Aeronautics 2024年第3期37卷 77-91页

作者： Nanxuan QIAO Tielin MA Xiangsheng WANG Jie WANG Jingcheng FU Pu XUE School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Institute of Unmanned System Beihang UniversityBeijing 100191China Key Laboratory of Advanced Technology of Intelligent Unmanned Flight System Ministry of Industry and Information TechnologyBeijing 100191China School of Transportation Science and Engineering Beihang UniversityBeijing 102206China Beijing Institute of Space Long March Vehicle Beijing 100076China

The performance improvement of swarm drones through aerodynamic shape optimization may be challenging due to folded size constraints imposed by the specific launch ***,fixed-wing aircraft swarms can benefit from formation flight in terms of energy *** study introduces the concept of the"aerodynamic formation unit",which consists of two or three aircraft that form an inseparable unit of the *** the Unmanned Aerial Vehicle(UAV)distribution and wingtip vortex interference in the formation,two typical aerodynamic formation units are optimized by the variable-fidelity aerodynamic optimization method based on space *** aerodynamic characteristics of the formation UAVs that affect flight performance,such as lift-to-drag ratio(L/D ratio)and static stability are analyzed by Computational Fluid Dynamics(CFD)*** L/D ratio(cruising condition)of the following aircraft can be increased by 22.8%and 57.5%in the optimal units that involve two and three aircraft ***,this study conducts several CFD simulations for multi-aircraft formations formed by the units,which show that the average L/D ratio of the formation can be improved by more than 19%.These results verify the feasibility and effectiveness of the"aerodynamic formation unit"concept and the optimization framework for formation parameters.

关键词： Formation flight CFD Aerodynamic formation unit Wingtip vortices Foldable tandem-wing aircraft

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Portrait Matting via Semantic and Detail Guidance 1

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7th Asian Conference on Pattern Recognition, ACPR 2023

作者： Wang, Deming Gao, Changxin Sang, Nong Key Laboratory of Image Processing and Intelligent Control School of Artificial Intelligence and Automation Huazhong University of Science and Technology Wuhan China

ISBN: (数字)9783031476341

ISBN: (纸本)9783031476334

Portrait matting is a challenging computer vision task that aims to estimate the per-pixel opacity of the foreground human regions. To produce high-quality alpha mattes, the majority of available methods employ a user-supplied trimap as an auxiliary input. However, obtaining trimap is difficult, which restricts the application of these methods. Recently, trimap-free approaches have been developed, but the alpha quality is significantly lower than that of trimap-based methods due to the lack of guidance. In this paper, we propose a portrait matting framework via semantic and detail guidance. We use the mask obtained from portrait segmentation as semantic guidance to improve semantic understanding of portrait matting, and we present a detail encoder block to capture the low-level feature around the subject as detail guidance, which helps to refine alpha details, such as hair. The proposed approach achieves remarkable results on both composition and real-world benchmarks. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

关键词： Semantics

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Broadcast Gossip Algorithm for Nash Equilibrium Seeking of Nonaggregative Games

IEEE Transactions on Artificial Intelligence

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IEEE Transactions on Artificial Intelligence 2024年第5期5卷 2444-2452页

作者： Wang, Dong Wu, Feiyue Xu, Xiaopeng Wen, Changyun Lian, Jie Zhou, Jun Dalian University of Technology Key Laboratory of Intelligent Control and Optimization for Industrial Equipment of Ministry of Education School of Control Science and Engineering Dalian116024 China Nanyang Technological University School of Electrical and Electronic Engineering 639798 Singapore Xuzhou Heavy Machinery Company Ltd. Xuzhou221600 China

In this article, we focus on seeking the Nash equilibrium (NE) of nonaggregative games over a directed communication network. An asynchronous broadcast-based gossip algorithm is proposed, where each player broadcasts its own decision and estimates of other players' decisions to its out-neighbors. Then, the neighboring players update its respective decisions using its independent stepsize and estimates of other players' decisions by weighting its own and the received decision estimates from $(0,\,1)$. The almost surely convergence of the proposed algorithm with the diminishing stepsizes is presented by using a lemma and the property of the Kronecker product. Furthermore, the expected error bound between the NE and decisions for the proposed algorithm with constant stepsizes is presented with the increasing active probability of each player. Finally, two numerical examples are provided to illustrate the effectiveness of the proposed algorithm and the convergence rate comparison. © 2020 IEEE.

关键词： Heuristic algorithms

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Simulation analysis of erosion characteristics of slurry pipelines based on CFD-DDPM pipeline parameters 43

Simulation analysis of erosion characteristics of slurry pip...

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43rd Chinese control Conference, CCC 2024

作者： Yuan, Haoran Wu, Jiande Xiong, Xin Yunnan University Yunnan Key Laboratory of Intelligent Systems and Computing Yunnan Kunming650500 China Kunming University of Science and Technology Faculty of Information Engineering and Automation Yunnan Kunming650500 China Kunming University of Science and Technology Yunnan Key Laboratory of Intelligent Control and Application Yunnan Kunming650500 China

ISBN: (纸本)9789887581581

In order to explore the impact of pipe diameter, bend-diameter ratio and bend angle on the erosion of slurry pipe, a numerical simulation method approach grounded in Computational Fluid Dynamics - Dense Discrete Phase Model (CFD-DDPM) is proposed. Firstly, the geometric models of bends with different pipe diameters, bend-diameter ratios, and bend angles are constructed;secondly, the slurry pipe erosion model based on Dense Discrete Phase Model (DDPM) is constructed;then, model validation is conducted on the slurry pipe erosion model to affirm the accuracy of the model;finally, the computational fluid dynamics method is employed to simulate the erosion and wear behavior of the pipeline, to investigate the impact of pipe diameter, bend-diameter ratio and bend angle on the erosion and wear of the slurry pipeline. At the same time, gray correlation analysis was also used to analyze the significant relationship between the three pipeline factors and erosion and wear. The results show that the main erosion area is not determined, with the change of the pipeline parameters, the most serious erosion area will move;the effect of different pipeline parameter variations on the erosion rate is different, in which the pipe diameter of the largest impact, the second largest bend-diameter ratio, the smallest impact of the bend angle. Therefore, in the design of slurry pipeline, should first consider the influence of pipe diameter factors. © 2024 Technical Committee on control Theory, Chinese Association of Automation.

关键词： Slurry pipelines

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Feature Alignment Transformer for Cross-domain Radio Frequency Fingerprint Identification 24

Feature Alignment Transformer for Cross-domain Radio Frequen...

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24th IEEE International Conference on Communication technology, ICCT 2024

作者： Wang, Yatong Wen, Zhongyi Cao, Bin Yan, Mu Song, Changqing Beijing Institute of Technology School of Information and Electronics Beijing100081 China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing100191 China University of Electronic Science and Technology of China Chengdu611731 China Beijing University of Posts and Telecommunications Beijing100876 China

ISBN: (纸本)9798350363760

Radio Frequency Fingerprint Identification (RFFI) has emerged as an effective device authentication paradigm, offering non-cryptographic, tamper-proof, and lightweight solutions for IoT networks. However, conventional deep learning-based RFFI schemes often experience significant performance degradation in cross-domain scenarios due to the distribution shift between training and test datasets, known as the cross-domain RFFI problem. To address this issue, we propose FATransformer, a novel framework for cross-domain RFFI, which comprises four key modules: data preprocessing, transformer backbone, feature alignment, and automatic tuning. Additionally, we establish a theoretical relationship between target domain error bounds and domain discrepancies to support the design of the feature alignment method. Extensive experiments on real-world datasets demonstrate FATransformer's superior accuracy in multiple cross-domain RFFI tasks compared to baselines. © 2024 IEEE.

关键词： Deep learning

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A PSO-LSTM-based Method for Spatial Target Orbit Phase Prediction

A PSO-LSTM-based Method for Spatial Target Orbit Phase Predi...

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Computer Vision, Image and Deep Learning (CVIDL), International Conference on

作者： Zonghua Qu Chunling Wei Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control Engineering Beijing China

As space becomes increasingly crowded and the orbital space environment gradually deteriorates, countries have gradually begun to pay attention to the in-orbit security of spacecraft. The timely and accurate sensing of space threats can effectively guarantee the in-orbit safety of our spacecraft. The orbital phase prediction for space targets is an important problem in the field of space situational awareness. In this paper, we propose a PSO-LSTM-based orbital prediction method for space targets, which has an accuracy rate of over 88.7% for different phases of orbital prediction.

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Dynamical Modeling and Dynamic Characteristics Analysisof a Coaxial Dual-Rotor System

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Journal of Dynamics, Monitoring and Diagnostics 2024年第2期3卷 99-111页

作者： Yubin Yue Hongjun Wang Shenglun Zhang China Academy of Machinery Science and Technology Group Co. Ltd.BeijingChina School of Mechanical and Electrical Engineering Beijing Information Science and Technology UniversityBeijingChina Key Laboratory of Modern Measurement and Control Technology Ministry of EducationBeijing Information Science and Technology UniversityBeijingChina Beijing International Science and Technology Cooperation Base of High-end Equipment Intelligent Perception and Control Beijing Information Science and Technology UniversityBeijingChina

The dual-rotor structure serves as the primary source of vibration in aero-engines. Understanding itsdynamical model and analyzing dynamic characteristics, such as critical speed and unbalanced response, arecrucial for rotor system dynamics. Previous work introduced a coaxial dual-rotor-support scheme for aeroengines,and a physical model featuring a high-speed flexible inner rotor with a substantial length-to-diameter ratiowas designed. Then a finite element (FE) dynamic model based on the Timoshenko beam elements and rigid bodykinematics of the dual-rotor system is modeled, with the Newmark method and Newton–Raphson method used forthe numerical calculation to study the dynamic characteristics of the system. Three different simulation models,including beam-based FE (1D) model, solid-based FE (3D) model, and transfer matrix model, were designed tostudy the characteristics of mode and the critical speed characteristic of the dual-rotor system. The unbalancedresponse of the dual-rotor system was analyzed to study the influence of mass unbalance on the rotor system. Theeffect of different disk unbalance phases and different speed ratios on the dynamic characteristics of the dual-rotorsystem was investigated in detail. The experimental result shows that the beam-based FE model is effective andsuitable for studying the dual-rotor system.

关键词： coaxial dual-rotor system dynamical modeling dynamic characteristics analysis rotor dynamics

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Finite-Time Active Disturbance Rejection control for Electromagnetic Formation Flight in Near-Earth Orbit 2nd

Finite-Time Active Disturbance Rejection Control for Electr...

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2nd International Conference on the Frontiers of Robotics and Software Engineering, FRSE 2024

作者： Shen, Xixi Meng, Bin Hu, Jiangping Zhou, Qingrui School of Automation Engineering University of Electronic Science and Technology of China Chengdu611731 China Beijing Institute of Control Engineering Beijing100080 China University of Electronic Science and Technology of China Huzhou313000 China Qian Xuesen Laboratory of Space Technology China Academy of Space Technology Beijing100094 China

ISBN: (纸本)9789819631605

This paper investigates the position tracking control problem in electromagnetic satellite formation by utilizing the relative motion CW equation as the dynamic model. Firstly, a finite-time state feedback controller is derived using the adding a power integrator method, without considering external disturbances. This controller constitutes the feedback component of the composite controller. Subsequently, when the relative velocity of the system cannot be measured and is subject to external disturbances, a finite-time extended state observer is designed to estimate the relative velocity and disturbances of the system. The estimated disturbances serve as feedforward compensation, and the combination of the observer and the feedback control law achieves finite-time control without velocity measurements. Finally, it is proven that the proposed control law can achieve position tracking within a finite time. Numerical simulations at the end of the paper validate the theoretical analysis. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.

关键词： Disturbance rejection

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GraphLoc: Enhancing Fingerprint-Based Localization With Graph Representation Learning

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IEEE Internet of Things Journal 2025年第12期12卷 21593-21603页

作者： Zhang, Lingyan Qiu, Yuanfeng Wu, Shaohua Zhang, Tingting Zhang, Qinyu Heilongjiang University School of Electronics Engineering Harbin China HongKong University of Science and Technology Thrust of Artificial Intelligence Guangzhou China School of Electronics and Information Engineering Shenzhen China Guangdong Provincial Key Laboratory of Space-Aerial Networking and Intelligent Sensing Shenzhen China

For 6G inherent intelligent capability, deeplearning-based wireless localization will become a promising technology for offering commercial location-based services (LBS). Classical deep neural networks (DNN) have been designed to learn feature representation for localization tasks. However, due to the uncertainty of radio measurements with complicated wireless propagation, the existing solution has achieved unsatisfactory performance with environmental dynamics. To address this issue, we propose GraphLoc, a novel approach to enhancing fingerprint-based localization with graph representation learning which can encode the structural information underlying radio fingerprints for robust localization. We first adopt graph signal processing of CSI fingerprints to create an unweighted graph. GraphLoc transforms the tasks of location estimations into node classification in a constructed graph. Then, we develop multilayer graph attention networks with the residual structure (Res-GAT) to learn graph representation by collecting the neighboring node features and aggregating their neighboring embeddings. Furthermore, in order to guarantee and speed up our Res-GAT convergence, we propose an appropriate training strategy to overcome training difficulty and overfitting for improving the quality of graph representations. Finally, extensive experimental results in many typical indoor scenarios demonstrate that the GraphLoc system can achieve better accuracy than other comparative schemes, even with the robustness of environmental dynamics, effectively facilitating fingerprint-based localization for fully practical LBS. © 2025 IEEE.

关键词： Graph neural networks

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High thermoelectric properties of Cu_(2)TeeAg_(2)Te composite with Fe addition and non-stoichiometric Te

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Journal of Materiomics 2024年第1期10卷 37-44页

作者： Wenxiu Li Su Dun Bin Xiao Jun Wang Xinba Yaer Chun Ying Ye Li Xiaohuan Wang Huijun Kang School of Materials Science and Engineering Inner Mongolia University of TechnologyHohhot010051China Research and Development Center HUA Cloud Intelligent Healthcare Co.LtdShenzhen518000China College of Sciences Inner Mongolia University of TechnologyHohhot010051China Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian116024China

Cu_(2)Te-based materials are a type of superionic conductor belonging to the class of phonon-liquid elec-tron-crystal materials and have achieved high ZT values by doping and ***,it is easy to form copper vacancies in Cu_(2)Te which leads to an excessive carrier concentration and then results in a low Seebeck ***,controlling copper ion migration and optimizing carrier concen-tration is essential to improve the thermoelectric performance of Cu_(2)*** paper reports high-performance Cu_(2)TeeAg_(2)Te composite with high application value in the low-middle temperature re-gion,which is achieved by fine tuning the carrier concentration using Fe addition and non-stoichiometric Te,as well as controlling the thermal conductivity of composite.A high ZT of~1.2 is obtained in AgCu_(0.97)Fe_(0.03)Te_(0.96)at a low temperature of 573 ***,the phase transition mechanism of Cu_(2)TeeAg_(2)Te and its effect on the thermoelectric transport performance are revealed that go beyond nanostructuring and single-doping,which provides a strong theoretical basis for research and perfor-mance improvement of thermoelectric materials in this system.

关键词： Thermoelectric AgCuTe Fe addition Non-stoichiometric Te

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