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8th International Symposium of Space optical Instruments and Applications, ISSOIA 2023

作者： Yi, Jia Jiang, Huilin Wang, Xiaoyong Ying, Du Graduate School Changchun University of Science and Technology Changchun130022 China School of Physics Changchun University of Science and Technology Changchun130022 China Beijing Institute of Space Mechanics and Electricity Beijing100190 China National and Local Joint Engineering Research Center of Space Optoelectronics Technology Changchun University of Science and Technology Changchun130022 China Fundammontal Science On Space-Ground Laser CommunicationTechnology Laboratory Changchun University of Science and Technology Changchun130022 China Key Laboratory of Education Ministry Optoelectronics Measurement and Control and Optical Shapingba China

ISBN: (纸本)9789819767175

Spectral technology is one of the key means for long-distance non-contact detection and identification of materials. It is an important force for ground-based detection satellites which can play a role in monitoring satellite operation status and safety, and identifying satellite types except for radar. However, for complex targets detected at ultra long distances, the detection object is equivalent to a point source, and the distribution of surface materials is not clear. Usually, material spectral unmixing can only focus on the distribution of planar materials, making it difficult to analyze the target structure. This article uses the spectral BRDF function to construct a hyperspectral ray tracing rendering 3D representation method based on the relationship between illumination, target surface normals, and detection points. It obtains a 3D rendering of a single material on a composite target, laying the foundation for analyzing the structural features of long-distance point target detection. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Rendering (computer graphics)

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Quantitative Detection of Internal Defects in Objects Using Holographic Double Exposure

SSRN

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SSRN 2023年

作者： Fu, Yanjun Zuo, Pengfei Tian, Lu Li, Hailong Zhong, Kejun Huang, Yiliang Ma, Baiheng Yan, Zhanjun School of Measuring and Optical Engineering Nanchang Hangkong University Nanchang330063 China Science and Technology on Electro-optic Control Laboratory Luoyang471023 China

Recent years have witnessed an increasing demand for high-quality materials in all industries;therefore, internal defects are disastrous for maintaining the required industrial quality. In this study, qualitative and quantitative analysis of the internal defects of objects is conducted using differential holographic double-exposure and digital image processing techniques. The objects underwent thermal loading, and two holograms were recorded at different temperatures. Internal defects were qualitatively and quantitatively analysed by processing and comparing the interference fringes produced by removing and reproducing the two holograms via digital image processing. The fringes at the location of the sample defects differed from the changes in surrounding fringes, and the defect size was determined by fitting the fringe region at the defect location. Finally, the experimental results were validated using a structured light 3D measurement method to identify the size of the defects. Interesting results were obtained, with a maximum error of 9.637% for irregular defects and a minimum error of 3.528% for regular defects. © 2023, The Authors. All rights reserved.

关键词： Holograms

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A Novel Phase-Shifting Segmented Phase Coding Method for Absolute Phase Retrieval

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SSRN 2023年

作者： Fu, Yanjun Li, Hewu Tian, Shiyang Ma, Fuqing Jiang, Guangyu Ma, Baiheng Yan, Zhanjun School of Measuring and Optical Engineering Nanchang Hangkong University Nanchang330063 China Science and Technology on Electro-optic Control Laboratory Luoyang471023 China

The phase-coding method is widely used during 3D measurement for attaining absolute phase retrieval. However, traditional the phase-coding method still suffers from low accuracy and insufficient reliability. To address these issues, a phase-shifting segmented phase coding method was proposed in this work for absolute phase retrieval in complex object measurements, which specifically improved upon the segmented method of phase coding. Coding patterns with different phase-shifting were obtained by embedding the codeword into the phase-shifting phase. These patterns were also combined and arranged to create novel segmented coding patterns. In addition, this segmented encoding can be self-connected based on its different phase-shifting information to obtain the complete fringe order, achieving thus absolute phase retrieval of over 36 codewords. To solve the problem of the periodic misalignment of the wrapped phase and fringe order, the complementary phase coding method was encoded by the bidirectional coding method, and the separation method of the bidirectional coding was improved. From experimental results, it was demonstrated that the proposed method has high measurement accuracy and reliability. © 2023, The Authors. All rights reserved.

关键词： Profilometry

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Weakly Supervised Point Cloud Semantic Segmentation Based on Multidimensional Feature Fusion and Feature Representation

Weakly Supervised Point Cloud Semantic Segmentation Based on...

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Electrical Engineering and Automation (IFEEA), International Forum on

作者： Kai Gu Zhenjian Lv Wenjun Zhu Yang Yi Fanwen Jia Jun Ma College of Electrical Engineering and Control Science Nanjing Tech University Nanjing China Key Laboratory of Science and Technology on Electromagnetic Environmental Effects and Electro-Optical Nanjing China

In recent years, with the popularity of LIDAR, depth cameras and other devices and the development of intelligent robots, high-precision maps, smart cities and other fields, the demand for outdoor scene understanding and environment perception at large scales is also getting higher and higher, and 3D point cloud semantic segmentation technology is precisely one of the research focuses. However, the current 3D semantic segmentation system mainly relies on the use of fully labelled 3D scenes for training. It is time-consuming and costly to fully annotate 10 million or even hundreds of millions of point clouds. Inspired by the weakly supervised semantic segmentation of 2D scenes, state-of-the-art research has also started to use a small number of labels to segment 3D scenes first. However, the outdoor point cloud data in it is large in scale and covers a wide area, which is a great challenge for neural networks to understand the spatial structure at large scales; secondly, the information brought by sparse labels is very important, and the model needs to improve the utilisation of sparse signals.

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Research on Location Algorithm Based on SAR and Infrared Fusion 1

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International Conference on Autonomous Unmanned Systems, ICAUS 2021

作者： Yang, Yanjiao Qu, Guangzhou Li, Bo Ma, Meng Liu, ShuaiShuai Chi, QingXi Beijing Electro-Mechanical Engineering Institute Beijing China Science and Technology on Complex System Control and Intelligent Agent Coopration Laboratory Beijing China

ISBN: (数字)9789811694929

ISBN: (纸本)9789811694912

Aiming at the problem of sins cumulative error correction, a dual-mode navigation algorithm based on infrared and SAR information fusion is studied. Radar system can provide SAR image and range information, and can measure height under certain conditions, but it cannot work in front. Infrared system can provide infrared image and optical axis direction of infrared lens. Based on the satellite positioning algorithm, this paper studies a fusion algorithm of radar SAR image and infrared. The image matching and measurement results are used to navigate to correct the accumulated errors of sins. Simulation results show the effectiveness of the algorithm. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Radar imaging

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Design of Reinforcement Learning Environment for Multiple UAV Area Coverage Search

Design of Reinforcement Learning Environment for Multiple UA...

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International Conference on Autonomous Unmanned Systems, ICAUS 2021

作者： Sun, Yinjiang Zhang, Rui Liu, Xiaoheng Liang, Wenbao Xu, Cheng Beijing Electro-Mechanical Engineering Institute Beijing China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing China

ISBN: (纸本)9789811694912

Unmanned aerial vehicle (UAV) plays an increasingly important role both in civil and military fields. As a typical mission, area coverage search is a primary measure for reconnaissance and surveillance of unknown areas. Due to the limited information about the mission area, UAV needs adaptiveness to the dynamic changes of the area and makes decisions based on local observation. It puts higher demands on the response speed of UAV, and traditional planning methods are tough to be directly applied. The problem becomes more noticeable for multiple UAV because of the heterogeneous function and large scale, and new solutions are urgently required. In this paper, the feasibility of reinforcement learning (RL) for performing area coverage search is explored, and an environment is designed for RL training and evaluation. Simulation results show that multiple UAV can cooperate and perform the mission with pretty high coverage. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Unmanned aerial vehicles (UAV)

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TSSDN aviation prospect analysis

TSSDN aviation prospect analysis

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2024 International Conference on Image Processing and Artificial Intelligence, ICIPAl 2024

作者： Dai, Jun Zhao, Changxiao Sun, Yixuan Zou, Jie School of Safety Science and Engineering Civil Aviation University of China Tianjin300300 China Key Laboratory of Civil Aircraft Airworthiness Technology CAAC Tianjin300300 China National Key Laboratory of Space Based Information Perception and Fusion China Luoyang Institute of Electro-Optical Equipment of AVIC Luoyang471000 China

ISBN: (纸本)9781510681514

Time Sensitive Software Defined Networking (TSSDN) is a new network architecture that combines Time Sensitive Networking TSN and Software Defined Networking SDN with the common advantages of both. In this paper, TSSDN is compared with different airborne networks from different perspectives and time-triggered traffic delay analysis is performed. Finally, it analyzes the advantages of TSSDN in civil aviation in general and the perspective to be improved. © 2024 SPIE.

关键词： Software defined networking

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Dynamic event-triggered fault-tolerant cooperative resilient tracking control with prescribed performance for UAVs

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science China(Information sciences) 2024年第8期67卷 67-84页

作者： Rong YUAN Zhengcai AN Shuyi SHAO Mou CHEN Mihai LUNGU College of Automation Engineering Nanjing University of Aeronautics and Astronautics Science and Technology on Electro-optic Control Laboratory Faculty of Electrical Engineering University of Craiova Aerospace Engineering Doctoral School University Politehnica of Bucharest

In this paper, a resilient tracking control scheme with cooperative collision avoidance performance is studied for the fixed-wing unmanned aerial vehicle(UAV) leader-follower formation in the presence of actuator failures and external disturbances. Firstly, based on the control objectives of UAV formation tracking and collision avoidance, the transformation tracking errors are obtained using the prescribed performance control technique. Next, a fault detection mechanism is introduced to determine if there is the actuator fault. Subsequently, the event-triggered resilient fault observers are designed based on a dynamic eventtriggered mechanism to estimate actuator faults. Furthermore, the prescribed performance functions and the H∞ performance index are employed to ensure the UAV formation collision-free and mitigate the impact of disturbances. Moreover, the resilient controller is designed to minimize the effect of the perturbations for the control gain and the fault observer gain on the system. The stability of the system is also proven through the Lyapunov stability analysis, and the controller gains are calculated by solving the linear matrix ***, the validity of the proposed control strategy is demonstrated by the simulation analysis.

关键词： UAV formation cooperative collision avoidance event-triggered fault observer prescribed performance resilient control

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Identity Re recognition technology Based on Improved Lightweight ConvNetx Model 42

Identity Re recognition Technology Based on Improved Lightwe...

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42nd Chinese control Conference, CCC 2023

作者： Siting, Peng Lei, Li Zhu, Hongbo Jun, Ren Zhichao, Song Yang, Jiabing The Beijing Electro-Mechanical Engineering Institute Beijing China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing China Beihang University School of Electronics and Information Engineering Beijing China

ISBN: (纸本)9789887581543

In the engineering field, there is a requirement for re recognition, including the identity recognition of cooperative and non-cooperative targets, that is, different sensors shoot targets in the same scene, and the identity recognition of targets from two perspectives is required, also known as target accurate retrieval. This method is widely used in fields such as automatic driving and military strikes. In the actual application scenario, deploying the re-recognition algorithm on the embedded processor needs to ensure the real-time computing speed and accuracy, so the complexity of the deep learning algorithm must be reduced, and pruning and lightweight processing are required. In the engineering field, when the image acquired by the sensor is subject to natural interference such as cloud and fog weather or fire and smoke, the difficulty of re-recognition increases. This paper adopts the lightweight improvement of ConvNeXt network model, and fine-tuned it on the basis of its original feature extraction function, so that it can successfully migrate to infrared image classification and also complete the extraction of infrared image target detail distinguishing features, and at the same time introduce the alignment of similar targets in infrared cross-view recognition. In the original similarity calculation, the average value is directly obtained from the spatial dimension of the output feature layer, which is replaced by the weight of the position in each space for estimation. The feature information of the multi-view marine ship target is extracted from the multi-sensor marine image, and its similarity is calculated, so as to determine the identity, thus reducing the support conditions and reconnaissance costs, and improving the accurate detection and tracking ability under the diverse dynamic reconnaissance conditions. © 2023 Technical Committee on control Theory, Chinese Association of Automation.

关键词： Feature extraction

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Government environmental control measures on CO_(2) emission during the 2014 Youth Olympic Games in Nanjing:Perspectives from a top-down approach

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Journal of Environmental sciences 2022年第3期34卷 165-178页

作者： Cheng Hu Cheng Liu Ning Hu Jun Hong Xinyue Ai College of Biology and the Environment Joint Center for sustainable Forestry in Southern ChinaNanjing Forestry UniversityNanjing 210037China Yale-NUIST Center on Atmospheric Environment International Joint Laboratory on Climate and Environment Change(ILCEC)Nanjing University of InformationScience&TechnologyNanjing 210044China Jiangxi Province Key Laboratory of the Causes and Control of Atmospheric Pollution/School of Water Resources and Environmental Engineering East China University of TechnologyNanchang 330013China National Key Laboratory on Electromagnetic Environmental Effects and Electro-Optical Engineering Army Engineering UniversityNanjing 210022China

Strict air pollution control measures were conducted during the Youth Olympic Games(YOG)period at Nanjing city and surrounding areas in August *** event provides a unique chance to evaluate the effect of government control measures on regional atmospheric pollution and greenhouse gas *** previous studies have observed significant reductions of atmospheric pollution species and improvement in air quality,while no study has quantified its synergism on anthropogenic CO_(2)emissions,which can be coreduced with air *** better understand to what extent these pollution control measures have reduced anthropogenic CO_(2)emissions,we conducted atmospheric CO_(2)measurements at the suburban site in Nanjing city from 1^(st) July to 30^(th) September 2014 and 1^(st) August to 31^(st) August 2015,obvious decrease in atmospheric CO_(2)was observed between YOG and the rest *** coupling the a prioriemission inventory with atmospheric transport model,we applied the scale factor Bayesian inversion approach to derive the posteriori CO_(2)emissions in YOG period and regular *** indicate CO_(2)emissions from power industry decreased by 45%,and other categories also decreased by 16%for manufacturing combusting,and 37%for non-metallic mineral *** total anthropogenic CO_(2)emissions were 9.8(±3.6)×10^(9) kg/month CO_(2) for regular period and decreased to 6.2(±1.9)×10^(9) kg/month during the YOG period in Nanjing city,with a 36.7%*** scaling up to whole Jiangsu Province,anthropogenic CO_(2)emissions were 7.1(±2.4)×10^(10) kg/month CO_(2)for regular period and decreased to 4.4(±1.2)×10^(10)kg/month CO_(2) during the YOG period,yielding a 38.0%reduction.

关键词： Carbon dioxide Reduction measures Anthropogenic emissions Bayesian inversion

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