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16th UK-Europe-China Workshop on Millimetre Waves and Terahertz Technologies, UCMMT 2023

作者： Yao, Chenyang Wang, Hao Cao, Jianyin Li, Xiang Qi, Liang Tian, Zhen Nanjing University of Science and Technology Nanjing China Nanhu Laboratory Jiaxing China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing China

ISBN: (纸本)9798350339406

This paper proposed a new method of expanding the bandwidth of PUMA array. By attaching bottom-open vias below the coupling plate, lower operating frequency is available without increasing the profile. This design ultimately performs 8.1:1 bandwidth (2.59-21.0 GHz) at broadside, a scanning range of ±75° in the E-plane with 6.6:1 bandwidth (2.68-17.65 GHz), ±50° in the H-plane with 7.4:1 bandwidth (2.58-19.03 GHz) and ±60° in the D-plane with 7:1 bandwidth (2.6-18.2 GHz) at an overall profile of 0.054λL. © 2023 IEEE.

关键词： Bandwidth

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Airfoil Aerodynamic Force Prediction Based on Graph Neural Networks 43

Airfoil Aerodynamic Force Prediction Based on Graph Neural N...

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43rd Chinese control Conference, CCC 2024

作者： Wang, Guoqing Cao, Junzhe Dalian University of Technology Control Science and Engineering Dalian116024 China Dalian University of Technology Key Laboratory of Intelligent Control and Optimization for Industrial Equipment of Ministry of Education Dalian116024 China

ISBN: (纸本)9789887581581

Aerodynamic force prediction is an important application of deep learning in the field of fluid mechanics. In this paper, a light graph neural network model with residual connections named LRGCN is designed to speed the computational process of the aerodynamic prediction. Comparing with other graph convolutional networks, the LRGCN reduces redundant operations and introduces skip connections, overcomes the limitations of traditional machine learning methods that require geometric airfoil parameters. By using CFD simulation, a dataset of aerodynamic forces for airfoil profiles was generated, where the nodes and edges of the flow field grids are abstracted to build a graph structure for aerodynamic force prediction. This study takes variations of the airfoil shape and pitch angle into consideration, enabling the prediction of lift and drag to be fast. In the numerical experiments, the LRGCN achieves the result that normalized test set loss is around 10-3 and the R2 is higher than 90%, which exhibits stronger robustness and higher accuracy than three other current convolutional models. And the LRGCN runs 60 times faster than the normal CFD method for the same prediction task, which significantly reduces time costs. © 2024 Technical Committee on control Theory, Chinese Association of Automation.

关键词： Computational fluid dynamics

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Design of wideband circularly polarized horn antenna for millimeter wave applications 15

Design of wideband circularly polarized horn antenna for mil...

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15th International Conference on Microwave and Millimeter Wave technology, ICMMT 2023

作者： Quan, Shuanglong Tian, Zhen Li, Xiang Qi, Liang Wang, Hao Nanjing University of Science and Technology Nanjing China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing China Nanhu Laboratory Jiaxing China

ISBN: (纸本)9798350338874

In this paper, a millimeter-wave (mmW) wide band right-handed circularly polarized (RHCP) horn antenna is designed based on a polarizer with two 90 degree slots loaded on the inner wall of a circular waveguide. The antenna is fed by a standard rectangular waveguide WR-10 waveguide port, and the antenna excitation signal is converted from linear to circular polarization by a circular polarizer. The principle of the antenna is analyzed, the model is simulated and the parameters are optimized, and the design method for obtaining the left-handed circularly polarized (LHCP) antenna based on the RHCP antenna is given. The simulation results show that the reflectance of the antenna is not higher than -24.5 dB, the RHCP gain is greater than or equal to 13.0 dBi, and the axial ratio (AR) is not higher than 3 dB in the range of 84-110 GHz (26.8% relative bandwidth). The proposed antenna is broadband and circularly polarized, and can be widely used in broadband mmW applications. © 2023 IEEE.

关键词： Millimeter waves

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Flow Field Prediction of Variable Geometry using a Novel Deep CNN Model with Dual-Feature of Flow Regions 43

Flow Field Prediction of Variable Geometry using a Novel Dee...

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43rd Chinese control Conference, CCC 2024

作者： Zhang, Mai Cao, Junzhe Dalian University of Technology Control Science and Engineering Dalian116024 China Dalian University of Technology Key Laboratory of Intelligent Control and Optimization for Industrial Equipment of Ministry of Education Dalian116024 China

ISBN: (纸本)9789887581581

Flow field prediction of variable geometry aims for the precise prediction of varying flow fields with complex geometric shapes and their variations. By combining a novel deep convolutional neural network (CNN) model with a Computational Fluid Dynamics (CFD) method, the solution of the Navier-Stokes equation can be effectively approximated with a significant reduction in the corresponding computation time cost. This paper proposes an approach named AM UNet-3 for predicting the flow field of variable geometry, which can directly predict the expected flow field of new shapes after the training of deep CNN through extracting and identifying dual features of flow field regions: geometric information features and multi-class channel features. The AM UNet-3 is a convolutional neural network model that combines a U-Net variant structure with three independent decoders and attention mechanisms. The framework of U-Net can learn the complete numerical solutions of the N-S equations to velocity and pressure fields from ground-truth data. The three independent decoders are used to output the pressure field and the velocity components in the x-direction and y-direction respectively. The embedded channel attention and spatial attention mechanisms can enhance the ability of AM UNet-3 to extract fast-changing boundary layer characteristics. The performances of AM UNet-3, U-Net and UNet-3 are tested and compared on a dataset consisting of flow field data with 981 different geometric shapes. Experiment results show that AM UNet-3 gets the fastest inference and the lowest prediction error in the three methods. Compared with the standard CFD method, AM UNet-3 is able to speed up the computation more than three orders of magnitude. © 2024 Technical Committee on control Theory, Chinese Association of Automation.

关键词： Computational fluid dynamics

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Multi-frame Temporal Modeling for Multi-object Tracking in Satellite Video 2

Multi-frame Temporal Modeling for Multi-object Tracking in S...

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2nd IEEE International Conference on Signal, Information and Data Processing, ICSIDP 2024

作者： Chai, Bingqian Qiao, Tingting Xie, Baorong Wang, Jue Liu, Wenchao Beijing Institute of Technology National Key Laboratory of Science and Technology on Space-Born Intelligent Information Processing Beijing China Shanghai Aerospace Electronic Technology Institute Shanghai China

ISBN: (纸本)9798331515669

With the advancement of remote sensing technology, video satellites have played an increasingly important role in both military and civilian domains, and they are widely used in areas such as military guidance, intelligent transportation, and disaster response. Multi-object tracking (MOT) in satellite video is a crucial research topic in these fields and has made certain progress. However, due to the difficulty of tracking objects in complex scene and low resolution, current MOT methods face issues of low accuracy in satellite video. In this work, we propose a joint-detection-and-tracking method called multi-frame temporal MOT (MFT-MOT). Firstly, a heatmap guided multi-frame temporal modeling method is introduced to extract features with temporal semantic information while suppressing background noise. Then, we utilize a weights-shared encoder-decoder network to facilitate interaction of temporal and spatial information and capture inter-frame object motion tracks at low resolution. Experiments on SAT-MTB dataset shows the effectiveness of our method. © 2024 IEEE.

关键词： Object tracking

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Design of millimeter wave wideband circularly polarized horn antenna based on rectangular waveguide polarizer 15

Design of millimeter wave wideband circularly polarized horn...

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15th International Conference on Microwave and Millimeter Wave technology, ICMMT 2023

ISBN: (纸本)9798350338874

In this paper, a millimeter wave (mmW) wide band right-handed circularly polarized (RHCP) horn antenna is designed with a polarizer in the form of a rectangular waveguide (RW). The antenna is fed by a standard RW WR-10 waveguide port. The designed polarizer can convert the antenna excitation signal from linearly polarized (LP) to circularly polarized (CP). The antenna is analyzed, modeled and simulated. The simulation results show that the S11 ≤-22.13dB, the axial ratio (AR) ≤3dB and the RHCP gain ≥15dBi in the range of 35.3% relative bandwidth (77GHz-110GHz). The proposed antenna is broadband and circularly polarized, and would be widely used in satellite communications and 5G mmW communications. © 2023 IEEE.

关键词： Millimeter waves

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Finite-time Prescribed Performance control with RBFNN for the HFV Longitudinal Model 41

Finite-time Prescribed Performance Control with RBFNN for th...

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第41届中国控制会议

作者： Yuan Zhang Wanwei Huang Kunfeng Lu Honghao Zhong Beijing Aerospace Automatic Control Institute National Key Laboratory of Science and Technology on Aerospace Intelligent Control

ISBN: (数字)9789887581536

ISBN: (纸本)9781665482561

A method for designing the finite-time prescribed performance controller with RBFNN(Radial Basis Function Networks) is proposed for the HFV(Hypersonic Flight Vehicle) longitudinal attitude systems with parameters uncertainties and time-varying ***,the appointed-time prescribed performance functions for outer-loop and inner-loop are designed respectively,which aims to restrain the transient and steady-state performance of command tracking *** with the traditional prescribed performance function,the proposed method can guarantee that the errors convergence to the set stability precision at the appointed ***,the error-transform function is applied to transform the guidance command errors into un-limited boundary,which can ensure the error satisfy the constraint condition by means of controlling the transformed ***,the virtual control law of outer-loop subsystem and the actual control law of inner-loop subsystem are designed independently,and the lumped disturbances are estimated by the RBFNN,a novel finite-time tracking differentiator is applied to avoid the 'explosion of terms' problem in the control law design ***,comparative simulations with parametric uncertainties and time-varying disturbance are performed to demonstrate that the proposed method in this paper can effectively satisfy the prescribed performance constraints.

关键词： Hypersonic flight vehicle Lumped Disturbance Finite-time control Radial Basis Function Networks Finite-time Tracking Differentiator

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Application of Grey Wolf Optimization Algorithm in Tuning controller Parameters of Hypersonic Vehicle 41

Application of Grey Wolf Optimization Algorithm in Tuning Co...

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第41届中国控制会议

作者： Can Tian Shaobo Ni Zhaolei Wang Yuan Zhang National Key Laboratory of Science and Technology on Aerospace Intelligent Control Beijing Aerospace Automatic Control Institute

ISBN: (数字)9789887581536

ISBN: (纸本)9781665482561

There are many adjustable parameters in the control method of predictive sliding mode control(PSMC) law and linear extended state observer(LESO) for hypersonic vehicle speed and altitude,and the adjustable parameters influence each other on the control effect,and the speed and altitude channels of the aircraft are coupled with each other,so the controller parameters cannot be independently tuned.A method of automatically tuning controller parameters by using grey wolf optimization(GWO) algorithm is ***,the fitness function containing the desired control effect is designed,and then the appropriate number of search agent and iteration times are *** simulation results show that the control effect of the controller with GWO tuning parameters is obviously better than that of the controller with experience tuning parameters,and the expected control effect can be achieved under the condition of adding parameter deviation and actuator limitation.

关键词： predictive sliding mode control linear extended state observer Grey Wolf optimization algorithm Auto-tuning controller parameters

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Low-Profile Tightly Coupled Dipole Array Loaded with Double-Layer Split Rings 16

Low-Profile Tightly Coupled Dipole Array Loaded with Double-...

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16th UK-Europe-China Workshop on Millimetre Waves and Terahertz Technologies, UCMMT 2023

作者： He, Chao Wang, Hao Quan, Shuanglong Tian, Zhen Li, Xiang Qi, Liang Nanjing University of Science and Technology Nanjing China Nanhu Laboratory Jiaxing China Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing China

ISBN: (纸本)9798350339406

A novel split ring (SR) wide-angle impedance matching (WAIM) printed on a double-layer PCB was designed to replace the dielectric slabs WAIM or frequency selective surface (FSS) WAIM with high profile. The proposed WAIM is designed together with tightly coupled dipole array (TCDA). Consequently, TCDA loaded with the proposed double-layer SR achieves a impedance bandwidth of 8.5:1(2.12-18 GHz ) with active VSWR3.2 at broadside;while scanning up to {60°,75°}in E-plane, a bandwidth of {8.2:1 (2.17-17.91GHz) , 6.1:1(2.91-17.43GHz)} is achieved;while scanning up to 45°in H-plane, a bandwidth of 6.8:1(2.55-16.77GHz) is achieved. Compared to the FSS loaded TCDA with a 0.078λl profile, the double layer SR loaded TCDA can ensure wideband, wide-angle scanning capability with a lower profile of 0.058λl (λl is the free-space wavelength at the lowest frequency). © 2023 IEEE.

关键词： Frequency selective surfaces

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A Survey on Negative Transfer

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IEEE/CAA Journal of Automatica Sinica 2023年第2期10卷 305-329页

作者： Wen Zhang Lingfei Deng Lei Zhang Dongrui Wu the Key Laboratory of the Ministry of Education for Image Processing and Intelligent Control School of Artificial Intelligence and AutomationHuazhong University of Science and TechnologyWuhan 430074China IEEE the School of Microelectronics and Communication Engineering Chongqing UniversityChongqing 400044China

Transfer learning(TL)utilizes data or knowledge from one or more source domains to facilitate learning in a target *** is particularly useful when the target domain has very few or no labeled data,due to annotation expense,privacy concerns,***,the effectiveness of TL is not always *** transfer(NT),i.e.,leveraging source domain data/knowledge undesirably reduces learning performance in the target domain,and has been a long-standing and challenging problem in *** approaches have been proposed in the literature to address this ***,there does not exist a systematic *** paper fills this gap,by first introducing the definition of NT and its causes,and reviewing over fifty representative approaches for overcoming NT,which fall into three categories:domain similarity estimation,safe transfer,and NT *** areas,including computer vision,bioinformatics,natural language processing,recommender systems,and robotics,that use NT mitigation strategies to facilitate positive transfers,are also ***,we give guidelines on NT task construction and baseline algorithms,benchmark existing TL and NT mitigation approaches on three NT-specific datasets,and point out challenges and future research *** ensure reproducibility,our code is publicized at https://***/chamwen/NT-Benchmark.

关键词： Domain adaptation domain similarity negative transfer positive transfer transfer learning

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