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Acta Mechanica Sinica 2024年第1期40卷 44-53页

作者：韦小丁张鹏马瑜薇刘俊杰於中良丛超男 State Key Laboratory for Turbulence and Complex System Department of Mechanics and Engineering ScienceCollege of EngineeringPeking UniversityBeijing100871China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing100083China Department of Engineering Mechanics Beijing University of TechnologyBeijing100124China College of Mechanical Engineering Yangzhou UniversityYangzhou225127China College of Science China Agricultural UniversityBeijing100083China

在本工作中,我们通过直流电沉积方法制备了含有不同体积比的(220)取向垂直纳米孪晶异质结构的铜薄膜,并表征了其力学性能.单轴拉伸测试表明,当垂直纳米孪晶的体积比增加时,机械性能显著提高:具有88%垂直孪晶的薄膜的极限拉伸强度为455 M... 详细信息

在本工作中,我们通过直流电沉积方法制备了含有不同体积比的(220)取向垂直纳米孪晶异质结构的铜薄膜,并表征了其力学性能.单轴拉伸测试表明,当垂直纳米孪晶的体积比增加时,机械性能显著提高:具有88%垂直孪晶的薄膜的极限拉伸强度为455 MPa,约比等轴晶粒铜薄膜的强度高83%.通过对拉伸后样品进行高分辨电子显微镜表征,并辅以分子动力学模拟,我们揭示了含有等轴晶粒和垂直纳米孪晶的特殊异质结构有助于激活铜薄膜材料内部多种模式的滑移系统,并导致更高的位错密度,从而在赋予材料更强的机械强度和加工硬化率的同时,不会显著损失材料的韧性.

关键词：纳米孪晶高分辨电子显微镜极限拉伸强度异质结构铜薄膜等轴晶粒滑移系统强化机制

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Research on Multi-target Association Tracking Algorithm Based on IMM

Research on Multi-target Association Tracking Algorithm Base...

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International Conference on Autonomous Unmanned systems, ICAUS 2021

作者： Siting, Peng Lei, Li Yichao, Ma Jun, Ren Beijing Electro-Mechanical Engineering Institute Beijing100074 China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing100074 China

ISBN: (纸本)9789811694912

Radar sensors are important detection and tracking equipment in national defense work. There are multiple targets in actual combat scenarios. It is necessary to quickly and accurately capture suspicious targets in the reconnaissance area and track them in real time. complex electromagnetic interference conditions and multi-target tracking requirements pose a great challenge to track correlation. This paper establishes a multi-target maneuver scenario and uses a joint probabilistic data interconnection algorithm based on interactive multi-model (IMM) to perform multi-target tracking. Correlation tracking, simulation results show that the algorithm is used to correlate the target maneuver and measurement information with good accuracy. Interactive multi-model filtering can mix the estimation results of each filter to generate a fused state estimation result. The description of the model is more accurate, which improves the tracking accuracy and tracking stability of the algorithm. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Kalman filters

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Remote Sensing Image Object Detection Algorithm Based on Receptive Field Enhancement

Remote Sensing Image Object Detection Algorithm Based on Rec...

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International Conference on Autonomous Unmanned systems, ICAUS 2021

作者： MingJun, Liu Yun, Zhang Rui, Zhang Cheng, Xu Beijing Electro-Mechanical Engineering Institute Beijing10074 China Science and Technology on Complex System Control and Intelligent Agent Corporation Laboratory Beijing10074 China

ISBN: (纸本)9789811694912

Small object detection algorithm is always a difficult research topic in remote sensing images. A remote sensing image object detection algorithm which is based on receptive field enhancement is proposed in this paper. Firstly, the backbone network is the SSD net. In order to form the feature map pyramid, the receptive field enhanced convolution module is added in feature extraction. Then, the feature maps of the low-level and the high-level are spliced, so he output feature map retains the rich context information. Because it contains the information in the low-level feature map and the high-level feature map, which are location information and semantic information, respectively. Finally, based on the idea of dilated convolution, the receptive field enhancement module is designed to make the receptive field of the feature map larger. And the feature information is filtered to reduce the aliasing effect when the feature map is spliced. After the experimental result on remote sensing image dataset NWPU vhr-10, the average detection accuracy of the algorithm is 90%, which improves the object detection accuracy, especially the detection accuracy of the small objects. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Convolution

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Evaluation of Joint Information Environment Service Capability of Space-based Network Information system Based on ANP-Fuzzy Comprehensive Evaluation Method 10

Evaluation of Joint Information Environment Service Capabili...

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10th IEEE Joint International Information technology and Artificial Intelligence Conference, ITAIC 2022

作者： Han, Chi Jian, Ping Xiong, Wei Fu, Jingyu Aerospace Information Institute Space Engineering University Beijing China Science and Technology on Complex Electronic System Simulation Laboratory Space Engineering University Beijing China

ISBN: (数字)9781665422079

ISBN: (纸本)9781665422079

In the increasingly systematic and networked environment of aerospace equipment, the space-based information service capability is not only affected by the platform and payload capacity of the mission spacecraft, but also increasingly restricted by the network characteristics and network environment for space-based information acquisition. In this context, the joint information environment of the space-based network information system is constructed (JIESNIS). The service capability evaluation index system of JIESNIS is constructed pertinently. Analytic Network Process (ANP) and fuzzy comprehensive evaluation method are combined to evaluate the service capability of JIESNIS. Based on the background of the space-based network information system joint information environment support operation under the customized and active service mode, the simulation model is constructed. The proposed ANP-Fuzzy comprehensive evaluation method is adopted to evaluate the capability JIESNIS, meanwhile the effectiveness of the method is verified. © 2022 IEEE.

关键词： Information services

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Error Modeling Method of Aircraft HWIL Simulation system Based on BP Wavelet Neural Network 18th

Error Modeling Method of Aircraft HWIL Simulation System Ba...

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18th Chinese Intelligent systems Conference, CISC 2022

作者： Tong, Jiahui Liu, Jin Li, Jing Zhang, Qing Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing100190 China Beijing Electro-Mechanical Engineering Institute Beijing102299 China

ISBN: (纸本)9789811962028

In order to ensure the confidence of hardware-in-the-loop(HWIL) simulation results, the simulation equipment and system are required to simulate the realistic flight environment;However, the additional error introduced by the simulation system in the guidance and control loop should be minimized. By studying the error model of the aircraft HWIL simulation system and analyzing the impact of the HWIL simulation system on the guidance and control quality, we can recognize the real performance of the guidance and control system, find out the key factors affecting the performance of the HWIL simulation system, provide decision-making basis for the development of simulation equipment, and improve and enhance the reliability of the simulation system. Based on BP wavelet neural network, the mathematical modeling of the aircraft HWIL simulation system error is carried out, and the modeling method and process are introduced in detail. A new method of aircraft HWIL simulation system error modeling with input and output data is proposed, and the applicability of modeling method is analyzed, and satisfactory accuracy results are obtained. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Errors

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Impact Analysis of Passive Multi- False Targets to Phased Array Radar Resources 15

Impact Analysis of Passive Multi- False Targets to Phased Ar...

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

作者： Hao, Guo-Qing Feng, De-Jun Cheng, Bi-Qin Wang, Jun-Jie Wang, Ling National University of Defense Technology The State Key Lab. of Complex Electromagnetic Environ. Effects on Electronics and Information System College of Electronic Science Changsha410073 China Unit 95861 of Pla Jiuquan735000 China

ISBN: (纸本)9798350338874

The phase-switched screen (PSS) can change the reflected echo of the target through a certain control method, thereby generating false targets. The study of material properties and the impact of materials on radar has attracted a lot of attention from the academic community. However, there are few studies on the influence of signal echo changes caused by artificial surface metamaterials on radar resources. In this paper, using PSS to change radar echo information to generate false targets in the Doppler frequency domain. Then the multi-false targets jamming effect on radar resources and multi-target tracking is analyzed. Simulation results show that these targets can consume radar search and tracking resources, generate a large number of temporary trails. This research is beneficial to the application of PSS for interference radar resources. © 2023 IEEE.

关键词： Target tracking

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Study on the Radio Frequency Simulation Method of Moving Ship for UAV-Borne Imaging Radar 18th

Study on the Radio Frequency Simulation Method of Moving Shi...

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18th Chinese Intelligent systems Conference, CISC 2022

作者： Diao, Guijie Gong, Ningbo Ni, Hong Liu, Zhe Tong, Jiahui Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing100190 China Beijing Electro-Mechanical Engineering Institute Beijing100083 China

ISBN: (纸本)9789811962257

A radio-frequency (RF) simulation method for UAV-borne imaging radar for moving ships at the sea-surface is proposed, which mainly solves the RF radar echo simulation problem for moving target at sea-surface. Based on the electromagnetic (EM) scattering model of sea-surface and ship target, the time-varying sea-surface scattering echo and moving ship target scattering echo are established respectively. Then, the scattering echo of a composite scene consisting of sea-surface background and ship-target is obtained by vector summation. Finally, the RF simulation system based on microwave anechoic chamber is constructed, and the simulation tests are carried out. Simulation results are presented to demonstrate the validity and applicability of the proposed method. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Radar imaging

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Research on Cooperative Multi-constraint Guidance Law for Leader-Follower Multi-aircraft 21st

Research on Cooperative Multi-constraint Guidance Law for Le...

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21st Asia Simulation Conference, AsiaSim 2022

作者： Xin, Du Guijie, Diao Zhe, Liu Ningbo, Gong Beijing Electro-Mechanical Engineering Institute Beijing100074 China Science and Technology On Complex System Control and Intelligent Agent Cooperation Laboratory Beijing100074 China

ISBN: (纸本)9789811991974

In this paper, the design and optimization of multi-aircraft cooperative guidance law with multi-constraint is studied for high-speed and large maneuvering targets. Firstly, the motion of the aircraft and the target are analyzed in the inertial coordinate system. The relative motion model and the corresponding state equation are established in a plane. Then, based on the sliding mode control method, the multi-constrained ballistic forming guidance law of the lead aircraft is designed to make it hit the target in multiple dimensions. Finally, the aircraft-to-target range and line-of-sight angle of the aircraft are selected as the state variables to be controlled, and the multi-constrained cooperative guidance law is designed for the follow aircraft. So that the motion of follow aircraft can track the lead aircraft accurately, the controlled state variables converges quickly, and hit the target at the same time until the end. The simulation results show that the leader-follower cooperative guidance law designed in this paper is effective for intercepting high-speed and large maneuvering targets. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Sliding mode control

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Radar Target Selection Strategy Based on Improved Subjective Bayesian Reasoning

Radar Target Selection Strategy Based on Improved Subjective...

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International Conference on Autonomous Unmanned systems, ICAUS 2021

作者： Li, Wen Pei, Hucheng Qu, Guangzhou Hao, Mingrui Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing100074 China Beijing Electro-Mechanical Engineering Institute Beijing100074 China

ISBN: (纸本)9789811694912

In order to deal with the influence of dilution passive decoy jamming on target selection of UAV radar, and to enable UAV radar have more independent decision-making ability to acquire the naval ship correctly in an ocean battlefield scene containing single real ship and multiple passive decoys, a method which established the mathematical simulation model of jamming scene, and used the model as the fitness function to calculate the adequacy measurement parameters of subjective Bayesian reasoning through genetic optimization algorithm is proposed. This method is applied to UAV radar target selection, compared with traditional target selection methods using single target feature, this method can improve the accuracy of ship acquisition by comprehensive using multi-dimensional target features. Moreover, this method can further improve the joint acquisition accuracy by setting multiple adequacy measurement parameters for different radars, which prove that the method can achieve the purpose of improving the success rate of UAV radar against dilution passive decoy jamming. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Radar

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A Novel Attitude Controller for Hypersonic Aircraft Based on FR-PI2

A Novel Attitude Controller for Hypersonic Aircraft Based on...

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International Conference on Guidance, Navigation and Control, ICGNC 2020

作者： Fan, Jiajun Li, Tianyi Guo, Xian Hao, Mingrui Sun, Mingwei College of Artificial Intelligence Nankai University Tianjin300350 China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Bejing100074 China

ISBN: (纸本)9789811581540

Due to the uncertainties and various noises of the Hypersonic Aircraft(HA), traditional method of designing attitude controllers based on accurate models faces immense challenges. To solve those proposed urgent problems effectively, in this paper, a innovative data-driven RL algorithm called FR-PI2 is proposed for the task of Hypersonic Aircraft attitude control, wherein several key techniques are introduced. Firstly, Hypersonic Aircraft attitude control is transformed into a stochastic optimal control problem, and the numerical solutions of the proposed stochastic optimal control problem are obtained with a path-integral-based method, called Policy Improvement with Path Integrals(PI2). Secondly, a model-free policy parameterization method with PID controller is integrated into the PI2 algorithm to ensure a low dependency of the Hypersonic Aircraft system model. Thirdly, a brand-new sample filtration method is proposed to guarantee rapid convergence, and an online optimization technology called rolling optimization is applied to guarantee optimality and real-time performance. Two series of experiments are carried out and analyzed to demonstrate the outstanding performance of the FR-PI2 algorithm. © 2022, The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Reinforcement learning

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