检索结果-内蒙古大学图书馆

2023 International Conference on Frontiers of Ocean science and technology, ICFOST 2023

作者： Gao, Fei Xu, Fanghua Li, Zhenglin Qin, Jixing Ma, Shuqing Department of Earth System Science Ministry of Education Key Laboratory of Earth System Modeling Institute for Global Change Studies Tsinghua University Beijing100084 China School of Ocean Engineering and Technology Sun Yat-Sen University GUANGDONG Zhuhai519000 China State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing100190 China College of Meteorology and Oceanology National University of Defense Technology Changsha410073 China

Dynamic internal solitary wave (ISW) can cause significant underwater sound fluctuations. In this paper, the periodic characteristics of sound intensity fluctuations and related physical mechanisms are investigated in the scenario that an ISW train passing through the acoustic path from source to receivers. From simulation results and experimental data, it is shown that the sound intensity fluctuates quasi-periodically, and the predominant fluctuation frequency is associated with modal interference and modal intensity. The initial mode coefficients at the source and the mode coupling are responsible for the fluctuations of modal intensities, and one of the predominant fluctuation periods is the same as that of the ISWs. © Published under licence by IOP Publishing Ltd.

关键词： Solitons

来源：评论

学校读者我要写书评

暂无评论

Modelling and Analyses of the Range Gate Pull-off (RGPO) Effect on Radar Tracking

Modelling and Analyses of the Range Gate Pull-off (RGPO) Eff...

引用

Progress in Electromagnetic Research Symposium (PIERS)

作者： Yanfeng Wang Qihua Wu Tiehua Zhao Xiaobin Liu Feng Zhao Shunping Xiao State Key Laboratory of Complex Electromagnetic Environmental Effects on Electronics and Information System College of Electronic Science and Technology National University of Defense Technology China

ISBN: (数字)9798350375909

ISBN: (纸本)9798350375916

Range gate pull-off (RGPO) Jamming disrupts tracking capability of radar system by strategically increasing the latency of radar signal. Hence this kind of active deception jamming is widely adopted. The quantitative assessment and evaluation of RGPO Jamming effects on radar systems is of great significance for enhancing radar anti-jamming capabilities. However, difficulties exist in establishing a mathematical model for analyzing the jamming effects through theoretical analyses. Both the complexity of different radar systems and randomness of radar tracking processes add to this challenge. These factors result in substantial workload to analyze jamming effects. Considering these challenges, a modelling method for RGPO effects on radar based on digital simulation results is introduced in this study. Firstly, the radar range tracking model was established. Through the qualitative analyses of the process of RGPO jamming effect and the principle of affecting the tracking loop, it was found that the rate of a successful pulling off would show a precipitous drop after the pulling speed exceeds a certain threshold. This conclusion was verified in the simulation results of the RGPO effect simulation system. On this basis, to build the relationship between the maximum pull-off speed and the Jamming-to-Signal Ratio (JSR), a modelling method based on spline interpolation and least squares fitting was proposed in this study. The work contributes to a deeper understanding of the impact of RGPO Jamming on radar tracking, and provides valuable insights for bolstering radar countermeasures.

关键词： Interpolation Analytical models Tracking loops Fitting Digital simulation Radar Logic gates

来源：评论

学校读者我要写书评

暂无评论

Autonomous Traffic Prediction for LEO Satellite-Based IoT Based on Satellite Spatiotemporal Features Mapping

引用

IEEE Internet of Things Journal 2025年

作者： Gong, Lizeng Chen, Quan Yang, Lei Yin, Zhenglong Wang, Yi National University of Defense Technology State Key Laboratory of Space System Operation and Control College of Aerospace Science and Engineering Changsha410073 China Nanjing Research Institute of Electronics Technology Nanjing210013 China

The traffic prediction method for Low Earth Orbit (LEO) satellite-based Internet of Things (IoT) provides prior conditions for addressing challenges in resource allocation and management of LEO satellite-based IoT. However, traditional methods rely on the pre-generation of terrestrial centers, leading to substantial computational complexity and delays when applying prediction results to LEO satellite-based IoT. Therefore, achieving autonomous LEO satellite-based IoT traffic prediction is essential. Unlike the spatiotemporal features of terrestrial IoT, LEO satellite-based IoT traffic is influenced by both satellite dynamics and terrestrial user behavior. Fortunately, real IoT traffic information can be shared between adjacent satellites through Inter-satellite Links (ISL). Inspired by the above, this paper proposes, for the first time, an autonomous LEO satellite-based IoT traffic prediction method. A Spatiotemporal Fusion Neural Network (SFNN) employing a four-layer hybrid neural network architecture is designed to accommodate the unique spatiotemporal features of LEO satellite-based IoT traffic. The simulation results demonstrate that the proposed method has low computational complexity and achieves a better prediction performance than the five baseline methods in LEO constellations. Further simulations demonstrate that the proposed method achieves higher accuracy in large-scale LEO constellations, and the algorithm remains applicable under ISL instability and satellite failure conditions. © 2014 IEEE.

关键词： Resource allocation

来源：评论

学校读者我要写书评

暂无评论

AWNet: Negative obstacle semantic segmentation Network based on adaptive weight loss 22

AWNet: Negative obstacle semantic segmentation Network based...

引用

22nd IEEE International Conference on Industrial Informatics, INDIN 2024

作者： Zhao, Jiarui Yu, Guizhen Wang, Jie Wang, Zhangyu Zhang, Junjie Feng, Yunsong School of Transportation Science and Engineering Beihang University Beijing China State Key Lab of Intelligent Transportation System Beihang University Beijing China The Key Laboratory of Autonomous Transportation Technology for Special Vehicles Beihang University Beijing China Ministry of Industry and Information Technology Beihang University Beijing China Research Institute for Frontier Science Beihang University Hefei China Hefei innovation research institute of Beihang university Beihang University Hefei China State Key Laboratory of Pulsed Power Laser Technology National University of Defense Technology Heufei China

ISBN: (纸本)9798331527471

On roads, both vehicles and pedestrians will leave traces after passing by. Slight traces will not cause any trouble to the passing vehicles and pedestrians subsequently. However, there are certain potholes in the road that have been formed by repeated crushing of vehicles. It may cause mechanical damage to following vehicles and lead to accidents as vehicles get stuck in the potholes. Thus, the segmentation of negative obstacles is crucial for the safe driving of self-driving vehicles. This paper proposed an AWNet neural network to this end, and quantitative analyses were conducted based on the publicly available dataset DRNO. Specifically, a random cut-and-joint module (RCJ) was proposed to augment the dataset. The cross-entropy loss function was modified by adding an adaptive weight module, i.e., the adaptive weight cross-entropy loss function. It allows the model to focus on negative obstacles during implementation. Furthermore, this paper proposed a post-processing module for adaptive viewpoint conversion based on depth maps, which is capable of fusing depth maps and RGB images to convert the front view into a BEV viewpoint. The mAcc for Negative obstacle semantic segmentation can reach 78.39%, the mIoU can reach 73.21%, the mF1 can reach 79.23%. The experimental results reveal that the AWNet is able to state-of-the-art performance compared with other networks. © 2024 IEEE.

关键词： Semantic Segmentation

来源：评论

学校读者我要写书评

暂无评论

integration of SSPP Antenna and Vivaldi Arrays for 5G Sub-6 GHz and Millimeter-Wave Applications

引用

IEEE Antennas and Wireless Propagation Letters 2025年

作者： Cheng, Houyuan Li, Shangru Fu, Yang Yang, Helin Wu, Jiong Zhou, Xiangli Shi, Xintong Central China Normal University College of Physical Science and Technology Wuhan430079 China State Key Laboratory of Complex Electromagnetic Environmental Effects on Electronics and Information System National University of Defense Technology China

An integrated antenna system covering 5G Sub-6 GHz and millimeter-wave bands is proposed, combining a spoof surface plasmon polariton (SSPP) antenna and two Vivaldi arrays. The integrated design comprises three radiators: an SSPP array, a linear tapered slot (LTS), and Vivaldi arrays. The SSPP antenna (excited by port 1) operates in the Sub-6 GHz band (SUB: 4–4.9 GHz and 5.3–6 GHz) through its SSPP array, while the LTS covers millimeter-wave band 1 (MMW1: 23–25.8 GHz). Dual Vivaldi arrays, symmetrically distributed on both sides of the antenna and excited by ports 2 and 3, operate in millimeter-wave band 2 (MMW2: 18–25.8 GHz). Measured results demonstrate average realized gains of 11 dBi (SUB), 13 dBi (MMW1), and 14 dBi (MMW2). This design shows potential for 5G communication and radar systems. © 2002-2011 IEEE.

关键词： Millimeter waves

来源：评论

学校读者我要写书评

暂无评论

The Effect of Coherent Frequency Diverse Array on Watson-Watt Direction-Finding system

The Effect of Coherent Frequency Diverse Array on Watson-Wat...

引用

Neural Networks, Information and Communication Engineering (NNICE), International Conference on

作者： Qiang Liu Kunlai Xiong Fucheng Guo Tao Xu State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System College of Electronic Science and Technology National University of Defense Technology Changsha China

Frequency diverse array(FDA) offer potential applications for enhancing the RF safety performance of FDA systems. This is due to the time-varying angle-distance coupling characteristics of the transmit beam map, which are caused by small frequency shifts between subarray elements. In this paper, we investigate the impact of coherent FDA signals on amplitude-based direction-finding systems, taking the Watson-Watt direction-finding system as an example. Firstly, we establish receiving model for direction finding of FDA signals. Secondly, we evaluate the error of the direction-finding system when using coherent FDA signals and analyze it with the Cramér-Rao lower bound(CRLB). Finally, we conduct a simulation analysis to validate the proposed theory. Both the theoretical analysis and simulation results demonstrate that coherent FDA signals can improve the radio frequency(RF) stealth performance. Specifically, the analysis and simulation results reveal that coherent FDA signals exhibit superior low-intercept performance for the Watson-Watt direction-finding system. These findings can be applied to all amplitude direction-finding systems.

关键词：

来源：评论

学校读者我要写书评

暂无评论

An ISAR Image Reconstruction Method via Signal Support Reweighted l1 Minimization

An ISAR Image Reconstruction Method via Signal Support Rewei...

引用

Signal, Information and Data Processing (ICSIDP), IEEE International Conference on

作者： Tiehua Zhao Qihua Wu Zhiming Xu Xiaofeng Ai Feng Zhao Shunping Xiao The State Key Laboratory of Complex Electromagnetic Environment Effects on Electronics and Information System College of Electronic Science and Technology National University of Defense Technology Changsha China

ISBN: (数字)9798331515669

ISBN: (纸本)9798331515676

The sparse aperture caused by data loss or unintentional interference is the actual problem in radar imaging process. Therefore, a compressed sensing (CS) based ISAR image reconstruction method with signal support aided is proposed in this paper. Firstly, the signal support is constructed from FFT-based imaging results. Then the signal support is introduced as a prior information into the reweighted function during the CS reconstruction. The simulation results show that, when the azimuth effective aperture ratio is as low as 30 % and signal-to-noise ratio (SNR) equals to -10 dB, the proposed method can obtain clear imaging results like that of complete aperture data. Besides, compared with the traditional CS reconstruction method, the number of false points in the reconstruction results by proposed method is greatly reduced.

关键词： Simulation Matching pursuit algorithms Imaging Radar imaging Apertures Reconstruction algorithms Minimization Sensors Image reconstruction Signal to noise ratio

来源：评论

学校读者我要写书评

暂无评论

Dynamic Analysis of Service-oriented Advanced avionics system based on Stochastic Evolutionary Game

Dynamic Analysis of Service-oriented Advanced Avionics Syste...

引用

Chinese Automation Congress (CAC)

作者： Zhaohui Liu Qingchun Liu Bingfei Li Shuo Zhang National Key Laboratory of Science and Technology on Avionics System Integration China National Aeronautical Radio Electronic Research Institute Shanghai China

Service-oriented advanced avionics system(SOAAS) is a complex network system with different stakeholders. Stake-holders are irrational behavior and may take aberrant behaviors in advanced avionics system. Different behavior will lead the avionics system to different states. In order to accurately predict the development trend of SOAAS and grasp its dynamic characteristics, stochastic evolutionary game theory is applied to study and analyze SOAAS in this paper. A multi-party game model is constructed to describe the behaviours of participant, and Ito stochastic differential equation is established based on stochastic theory to break through the limitation of replicator dynamics equation. The stability problem of SOAAS is effectively analyzed, and sufficient conditions of system stability are given. Simulation results show the correct and practicable of the established game model and analysis method.

关键词： Simulation Indium tin oxide Stochastic processes Games Aerospace electronics Mathematical models Stability analysis

来源：评论

学校读者我要写书评

暂无评论

Progress and applications of ghost imaging with classical sources: a brief review [Invited]

引用

Chinese Optics Letters 2024年第11期22卷 24-35页

作者： Weitao Liu Wenlin Gong Zhentao Liu Shuai Sun Zhenwu Nie Institute for Quantum Science and Technology College of ScienceNational University of Defense TechnologyChangsha 410073China Interdisciplinary Center of Quantum Information National University of Defense TechnologyChangsha 410073China Hunan Key Laboratory of Mechanism and Technology of Quantum Information Changsha 410073China School of Optoelectronic Science and Engineering Soochow UniversitySuzhou 215006China Key Laboratory of Advanced Optical Manufacturing Technologies of Jiangsu Province Soochow UniversitySuzhou 215006China Key Laboratory of Quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Wangzhijiang Innovation Center for Laser Aerospace Laser Technology and System DepartmentShanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China

Study on optical correlation function initiates the development of many quantum techniques, with ghost imaging(GI) being one of the great achievements. Upon the first demonstration with entangled sources, the physics and improvements of GI attracted much interest. Among existing studies, GI with classical sources provoked debates and ideas to the most *** better understanding and practical applications of GI, fundamental theory, various designs of illumination patterns as well as reconstruction algorithms, demonstrations and field tests have been reported, with the topic of GI very much enriched. In this paper, we try to sketch the evolution of GI, focusing mainly on the basic idea, the properties and superiority,progress toward applications of GI with classical sources, and provide our discussion looking into the future.

关键词： ghost imaging imaging systems coherence theory.

来源：评论

学校读者我要写书评

暂无评论

Supermaneuverable Flipping Control and Planning Based on Multi-Rotor Mode of Tilt-Rotor UAVs

Supermaneuverable Flipping Control and Planning Based on Mul...

引用

2024 IEEE International Conference on Robotics and Biomimetics, ROBIO 2024

作者： Wang, Hongpeng Zhang, Qinghao Fei, Yue Deng, Kun Liang, Jun Sun, Chuanyu Xu, Li Civil Aviation University of China The Key Laboratory of Civil Aviation Smart Airport Theory and System China College of Artificial Intelligence Nankai University Tianjin300071 China National University of Defense Technology Laboratory of Science and Technology on Integrated Logistics Support Changsha410073 China Institute of Intelligence Technology and Robotic Systems Shenzhen Research Institute Nankai University Shenzhen518083 China China Nuclear Power Technology Research Institute Co. Ltd Shenzhen518000 China

ISBN: (纸本)9781665481090

Maneuverability is a critical factor for UAV s to survive in high-intensity combat scenarios. Traditional UAV s typically operate in a stable motion state to ensure flight safety. However, in highly contested environments, special missions require high mobility while maintaining safety. Tilt-rotor UAV s, which combine the characteristics of fixed-wing and multi-rotor UAVs, can perform extreme maneuvers, such as high angles of attack and post-stall maneuvers, to rapidly change posture and complete tasks like positioning and defense. Therefore, integrating and optimizing safety and maneuverability metrics is necessary for enabling UAV s to achieve extreme maneuverability. In this paper, extreme maneuver planning and control for tilt-rotor UAV s are realized through a method based on third-order Bezier curve planning of body angular velocity. Experimental results demonstrate tilt-rotor UAVs can perform extreme super-maneuverable flips while maintaining overall process control. © 2024 IEEE.

关键词： Maneuverability

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：