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Optimization of the Internet of Remote Things Data Acquisition Based on Satellite UAV Integrated Network

China Communications 2023年第7期20卷 15-28页

作者： Yuanyuan Yao Dengyang Dong Sai Huang Chunyu Pan Shuo Chen Xuehua Li Key Laboratory of Information and Communication Systems Ministry of Information IndustryBeijing Information Science and Technology UniversityBeijing 100101China Key Laboratory of Modern Measurement&Control Technology Ministry of EducationBeijing Information Science and Technology UniversityBeijing 100101China Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

In order to achieve dependable and efficient data acquisition and transmission in the Internet of Remote Things(IoRT),we investigate the optimization scheme of IoRT data acquisition under the unmanned aerial vehicle(UAV)-low earth orbit(LEO)satellite integrated space-air-ground network,in which the UAV acquires data from massive Internet of Things(IoT)devices in special *** combine with the actual scenario,we consider two different data types,that is,delay-sensitive data and delay-tolerant data,the transmission mode is accordingly divided into two *** delay-sensitive data,the data will be transmitted via the LEO satellite relay to the data center(DC)in *** delay-tolerant data,the UAV will store and carry the data until the acquisition is completed,and then return to *** to nonconvexity and complexity of the formulated problem,a multi-dimensional optimization Rate Demand based Joint Optimization(RDJO)algorithm is *** algorithm first uses successive convex approximation(SCA)technology to solve the non-convexity,and then based on the block coordinate descent(BCD)method,the data acquisition efficiency is maximized by jointly optimizing UAV deployment,the bandwidth allocation of IoRT devices,and the transmission power of the ***,the proposed RDJO algorithm is compared with the conventional *** consequences demonstrate that the efficiency of IoRT data acquisition can be greatly improved by multi-parameter optimization of the bandwidth allocation,UAV deployment and the transmission power.

关键词： Internet of Remote Things dataacquisi-tion unmanned aerial vehicle LEO satellite

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Optimal crater landmark selection based on optical navigation performance factors for planetary landing

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Chinese Journal of Aeronautics 2023年第3期36卷 254-270页

作者： Yi XIU Shengying ZHU Rui XU Maodeng LI School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Autonomous Navigation and Control for Deep Space Exploration Ministry of Industry and Information TechnologyBeijing 100081China Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of EducationBeijing 100081China Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control EngineeringBeijing 100091China

Planetary craters are natural navigation landmarks that widely exist and are easily *** navigation based on crater landmarks has become an important autonomous navigation method for planetary *** to the increase in observed crater landmarks and the limitation of onboard computation,the selection of good crater landmarks has gradually become a research hotspot in the field of landmark-based optical *** paper designs a fast crater landmark selection method,which not only considers the configuration observability of crater subsets but also focuses on the influence on navigation performance arising from the measurement uncertainty and the matching confidence of craters,which is different from other landmark selection *** factor of measurement uncertainty,which is anisotropic,correlated and nonidentically distributed,is quantified and integrated into selection based on crater pairing detection and localization error *** addition,the concept of the crater matching confidence factor is introduced,which reflects the possibility of 2D projection measurements corresponding to 3D *** with the configuration observability factor,the crater landmark selection indicator is ***,the effectiveness of the proposed method is verified by Monte Carlo simulations.

关键词： Crater-based optical navigation Crater landmark selection Crater matching Measurement uncertainty Planetary landing

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Experimental study on the effect of underwater multiple degradation links on optical signal transmission: Experimental study on the effect of underwater multiple degradation links on optical signal transmission 6

Experimental study on the effect of underwater multiple degr...

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6th International Conference on Artificial Intelligence and Pattern Recognition, AIPR 2023

作者： Zhang, Jianlei Zhang, Pengwei Zhu, Yunzhou Tian, Yuxin School of Electronic Engineering Xi'an University of Posts and Telecommunications Xi'an710121 China Science and Technology on Underwater Information and Control Laboratory Xi'an710077 China

ISBN: (纸本)9798400707674

This paper presents an experimental investigation of the impact of various environmental factors, including temperature, salinity, and air bubbles, on the transmission of optical signals. A reception model was established to capture the degradation of the optical signal as it passes through multiple links. The fading of optical signals passing through different channels was quantified and analyzed. The findings highlight the distinct impacts of temperature, salinity, and air bubbles on the propagation of optical signals. Additionally, the study reveals that turbulence intensity plays a pivotal role in influencing the variability of the normalized amplitude of the received signal. © 2023 ACM.

关键词： Turbulence

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Coastal Regions Sea Surface Salinity Retrieval of SMAP MISSION Based on Light Gradient Boosting Model

Coastal Regions Sea Surface Salinity Retrieval of SMAP MISSI...

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2024 Photonics and Electromagnetics Research Symposium, PIERS 2024

作者： Song, Haoming Zhang, Yifan Zhang, Biao Lv, Yanfang Zhang, Lanjie Ministry of Information Industry Beijing Information Science and Technology University Key Laboratory of Information and Communication Systems China Ministry of Education Beijing Information Science and Technology University Key Laboratory of Modern Measurement and Control Technology China

ISBN: (纸本)9798350375909

Sea surface salinity (SSS) as an important indicator of ocean water circulation, affects global ecology and climate change. However, the accuracy of L-band satellite sea surface salinity retrieval products has been severely affected in coastal regions due to factors such as Radio Frequency Interference (RFI) and Land Sea Continuation (LSC). In this study, coastal regions observational data from the Soil Motion Active Passive (SMAP) satellite, and established the LGBM model for SSS retrieval. The results indicated that LGBM performed excellently in the retrieval of SSS in coastal regions. In comparison to in-situ SSS, the LGBM SSS demonstrated a mean bias (MB) of 0.11psu, a root mean squares error (RMSE) of 0.68psu. This paper also added the bias between LGBM SSS and in situ SSS for secondary correction of LGBM. This correction reduced the MB to 0.03psu, the RMSE to 0.54psu. This study affirms the feasibility of using LGBM for SSS retrieval in coastal regions. Future efforts will focus on integrating more auxiliary data that may influence SSS in coastal regions, aiming to further enhance the precision of the coastal regions' SSS retrieval product. © 2024 IEEE.

关键词： Radio interference

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Vertical array signal recovery method based on normalized virtual time reversal mirror

Vertical array signal recovery method based on normalized vi...

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2022 International Conference on information Processing in Ocean science and technology, ICIPOST 2022

作者： Li, P. Zhang, X.G. Zhang, X.Y. Liu, Y. Science and Technology on Underwater Test and Control Laboratory Dalian116013 China Dalian Scientific Test and Control Technology Institute Dalian116013 China

Focusing on the vertical array source signal recovery method, aiming at the estimation deviation caused by environment mismatch in the engineering application of virtual time reversal mirror technology, this paper proposes the normalized virtual time reversal technology through theoretical derivation and analyzes the performance of the virtual time reversal technology under the change of environment and signal-to-noise ratio through simulation. Finally, the practicability of the normalized virtual time reversal method and the effectiveness of model correction are verified through experimental data. The data processing results show that the source level estimation error of vertical array based on normalized virtual time reversal algorithm is less than 5.2dB. In the experimental environment of this paper, the correlation of signal spectral structure recovered by this method is about 5% higher than that by the traditional method. © Published under licence by IOP Publishing Ltd.

关键词： Signal to noise ratio

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Introducing ionic mediators to construct peak-splitting manganese oxide structures for efficient oxygen reduction reactions

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Journal of Materials science & technology 2024年第34期201卷 139-148页

作者： Haoliang Ma Xiong Li Mengmeng Tian Lanlan Li Xiaofei Yu Xinghua Zhang Zunming Lu Xiaojing Yang School of Materials Science and Engineering Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control TechnologyHebei University of TechnologyTianjin 300130China School of Artificial Intelligence and Information Technology Nanjing University of Chinese MedicineNanjing 210023China

Manganese oxides have received extensive attention in Oxygen Reduction Reaction(ORR)***-ever,the poor electrical conductivity and oxygen adsorption capacity of manganese oxides limit their development,so it is necessary to prepare catalysts with highly active *** propose a method to introduce an ionically conductive medium and induce structural distortion via thermodynamics,re-sulting in novel peak-splitting highly active structures for enhanced oxygen reduction *** the aid of refined structural analysis,High-angle annular dark-field(HAADF-STEM)imaging,and theoretical calculations,it is elucidated that this peak-splitting structure results from thermodynamically induced structural distortions and atomic *** introduction of the ionically conductive medium promotes the formation of Ag-O-Mn conductive bond bridges,which regulate the energy level matching of manganese oxides and oxygen *** thermodynamically induced structural distortion ex-poses new atomic planes in the material,and the creation of this highly active surface is accompanied by a redistribution of surface charges,which modulates the adsorption of manganese active sites with oxy-gen intermediates and greatly enhances the oxygen reduction ***,this Ag-OMS-2 with a novel split structure exhibits excellent activity at 0.836 V,superior to Pt/C kinetics and good *** preparation of such highly active structures is instructive for the development of manganese oxides.

关键词： Fuel cells Electrochemistry Manganese Structural distortion Ionically conductive medium

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Research on dynamic response behavior of the fuze with a combined fuze-warhead structure under different impact positions of bullets 4

Research on dynamic response behavior of the fuze with a com...

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4th International Conference on Defence technology, ICDT 2024

作者： Wang, Qiang Niu, Lanjie Fan, Chenyang Qv, Zhuojun Xv, Rui Science and Technology on Electromechanical Dynamic Control Laboratory Xi’an Institute of Electromechanical Information Technology Xi’an China

Aiming at the problem of unclear fuse detonation response in the process of different positions of the bullet impact detonator, to carry out research on the dynamic response behaviour of the fuse under the difference of the bullet impact position of the fuze-warhead combination structure. Through experiments and LS-DYNA numerical simulation, the influence of different positions of bullet impact booster on fuze reaction level and output pressure is analyzed. The results demonstrate that in the tests where the bullet made contact with the centre of the fuse, transmitting an explosive charge, the velocity of the bullet is 832 m/s, and the fuse exhibits a partial detonation level in response to the impact. The highest fuse response level occurs when the bullet strikes the centre of the pyrotechnic charge - partial detonation, the lowest fuse response level occurs when the bullet strikes the upper side of the pyrotechnic charge - burning, and the fuse response level occurs when the bullet strikes the lower side of the pyrotechnic charge - deflagration or explosion. The maximum fuse output pressure when the bullet strikes the centre of the pyrotechnic charge - 6.09 GPa, the minimum fuse output pressure when the bullet strikes the upper side of the pyrotechnic charge - 0.98 GPa, and the fuse output pressure when the bullet strikes the lower side of the pyrotechnic charge is 2.76 GPa. © 2024 Institute of Physics Publishing. All rights reserved.

关键词： Detonation

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Adjustable patch and feature prior token-based transformer for weakly supervised semantic segmentation

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International Journal of Computers and Applications 2024年第7期46卷 445-454页

作者： Li, Linjuan Zhang, Haoxue Xie, Gang Bai, Yanhong School of Electronic and Information Engineering Taiyuan University of Science and Technology Taiyuan China Shanxi Key Laboratory of Advanced Control and Equipment Intelligence Taiyuan China

Weakly supervised semantic segmentation is a challenging task, utilizing only low-cost weak supervision to produce pixel-level predictions. Existing transformer-based methods for weakly supervised semantic segmentation have some limitations: (1) Fixing patch size might destroy the structured semantics, which is unfriendly to objects of different scales, and (2) Ignoring the prior features when using multi-head attention mechanisms might lead to inaccurate segmentation localization. To tackle these issues, we proposed an effective transformer framework coupled with the adjustable patch and prior feature tokens, termed as APFPformer, in which an adjustable patch module is developed to split the image according to the area of the salient object for preserving the structured semantics in patches. A prior feature token module is devised to exploit the edge and texture information as prior tokens, ensuring the gain of discriminative representation. Additionally, a single-stage scheme is applied to reduce the computation and rapid segmentation process. Our experiments demonstrate the superiority of our approach over early methods, gaining competitive mean Intersection-over-Union scores of 67.9% on the PASCAL VOC2012 dataset and 40.2% on the MS COCO dataset. © 2024 Informa UK Limited, trading as Taylor & Francis Group.

关键词： Semantic Segmentation

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Mosaic Method for Bistatic Acoustic Images of Seafloor Based on Pixel Weighting 6

Mosaic Method for Bistatic Acoustic Images of Seafloor Based...

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6th International Conference on information Communication and Signal Processing, ICICSP 2023

作者： Su, Zhaohua Zhuo, Jie Sun, Chao School of Marine Science and Technology Northwestern Polytechnical University Shaanxi Key Laboratory of Underwater Information Technology Xi'an China

ISBN: (纸本)9798350339994

In a bistatic sonar imaging system for seafloor composed of a vertical transmitting array and a horizontally towed receiving array, the left-right ambiguity caused by the receiving array leads to false features in mosaicked image using a conventional method. In this paper, an improved image mosaic method based on pixel weighting is proposed. A sliding window is applied to filter the pixels in each frame that are above the mean value of the sub-window, and then the number of occurrences of each pixel is used as the weighted value for mosaicking images. Both numerical simulations and experimental results show that the proposed method can effectively suppress the ambiguities in the mosaicked image. © 2023 IEEE.

关键词： bistatic acoustic imaging image mosaicking left-right ambiguity pixel weighting

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Time-Varying Formation Tracking control of Heterogeneous Multi-Agent Systems With Intermittent Communications and Directed Switching Networks

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IEEE/CAA Journal of Automatica Sinica 2025年第1期12卷 294-296页

作者： Yuhan Wang Zhuping Wang Hao Zhang Huaicheng Yan the Shanghai Research Institute for Intelligent Autonomous Systems Tongji University the National Key Laboratory of Autonomous Intelligent Unmanned Systems the Frontiers Science Center for Intelligent Autonomous System of Ministry of Education the College of Electronic and Information Engineering the Department of Control Science and Engineering Tongji University the Key Laboratory of Advanced Control and Optimization for Chemical Processes of Ministry of Education the School of Information Science and Engineering East China University of Science and Technology

Dear Editor,This letter is concerned with the problem of time-varying formation tracking for heterogeneous multi-agent systems(MASs) under directed switching networks. For this purpose, our first step is to present so... 详细信息

关键词： Switches Topology Observers Formation control Event detection Switched systems Multi-agent systems control theory Autonomous systems Stability

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