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5th International Conference on Intelligent Computing, Communication and Devices, ICCD 2019

作者： Qi, Xiaogang Dong, Haijun Li, Hao Liu, Lifang School of Mathematics and Statistics Xidian University Xi’an710071 China School of Computer Science and Technology Xidian University Xi’an710071 China Science and Technology on Near-Surface Detection Laboratory The First Scientific Research Institute of Wuxi Wuxi214000 China

ISBN: (纸本)9789811558863

Energy-saving optimization has become one of the key research issues in the design of routing protocols for wireless sensor network (WSN), because most nodes in WSN have limited non-rechargeable battery power. Aiming at the problems of minimizing the energy consumption of data relay and maximizing network life in one-dimensional (1-D) queue networks, we propose a Sleep-based Opportunistic Routing (SOR) algorithm based on opportunistic routing. This algorithm not only fully considers the distance and residual energy of the nodes to protect the low-energy nodes, but also proposes a selection algorithm based on the sleep mechanism, which divides the state of the node into three states of sleep, switching and working. The simulation results show that SOR extends the network lifetime more effectively and enhances the network realizes energy saving and low-power consumption, and has the function of wireless communication connection. © 2021, The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Routing algorithms

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A High-Precision Method of Time Delay Estimation in Complex Environment 5th

A High-Precision Method of Time Delay Estimation in Complex ...

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5th International Conference on Intelligent Computing, Communication and Devices, ICCD 2019

作者： Qi, Xiaogang Yuan, Lieping Chen, Yu Liu, Lifang School of Mathematics and Statistics Xidian University Xi’an710071 China School of Computer Science and Technology Xidian University Xi’an710071 China Science and Technology on Near-Surface Detection Laboratory The First Scientific Research Institute of Wuxi Wuxi214000 China

ISBN: (纸本)9789811558863

Firstly, this method employs Gaussian fitting based on the phase transform generalized cross-correlation (PHAT-GCC) method to get a more precise location of the peak, which makes TDE precision into sub-sampling point level. Secondly, the post-processing algorithm of time delay based on mean and median is exploited to deal with abnormal fluctuation of TDE. The real-life data and MATLAB simulation show that the proposed method is obviously advantageous over the PHAT-GCC method on the precision of TDE and anti-noise performance under the complex environment. © 2021, The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Time delay

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Root inspired in situ interlocked interface for strength and ductility combination of refractory high-entropy alloys/Ni composites by activated sintering

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Materials science and Engineering: A 2025年 939卷

作者： Xiao Yang De Yang Hai Huang Shubang Wang Zehai Zhang Zhimin Liang Liwei Wang Zhenzhen Peng Ying Liu Dianlong Wang Hebei Key Laboratory of Material Near-Net Forming Technology School of Materials Science and Engineering Hebei University of Science and Technology Shijiazhuang 050018 China School of Materials Science and Engineering East China Jiaotong University Nanchang 330013 China Key Laboratory of Superlight Material and Surface Technology Ministy of Education College of Materials Science and Chemical Engineering Harbin Engineering University Harbin 150001 China School of Mechanical Engineering Yanshan University Qinhuangdao 066004 China

This work proposed a simple bionic-inspired strategy to in situ construct a root-like interfacial interlocked structure in the refractory high-entropy alloys (RHEA) particle-reinforced Ni matrix composites by activated sintering. The results showed that at the RHEA-Ni interface, Ni element preferred to aggregate inside the RHEA near the interface by grain boundaries (GBs) wetting and far away from the interface by GBs prewetting. Subsequently, the Ni-rich liquid-like film crystallized into Ni 3 (Ta, Nb), Ni 2 (Ta, Nb) phases due to relatively low Gibbs free energy change (Δ G ) and high diffusion rate, in situ forming root-like interlocked structure anchored on the RHEA particle. At the root-like interlocked interface, the Ni-Ta intermetallic compounds (IMCs) and BCC phase, serving as alternating hard and soft oriented phases, enhance the interlocked interface hardness and elastic modulus. The finite element method proved that the root-like interlocked structure reduced the demand for interfacial reaction layer strength and the degree of interfacial stress concentration. Compared to the pure Ni bulk, the 10 vol% RHEA/Ni composite obtains 41.8 % and 93.4 % in ultimate tensile strength (UTS) to 509 MPa and yield strength (YS) to 205 MPa, respectively, while maintaining an acceptable elongation of 15.8 %. This work offers a novel approach to in situ synthesize the bionic configuration interface structure for the enhanced interfacial bonding and optimized interfacial stress distribution of the Ni matrix composites.

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Sparse Multi-carrier Frequency Diverse Array Transmit Beampattern Optimization

Sparse Multi-carrier Frequency Diverse Array Transmit Beampa...

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Progress in Electromagnetic Research Symposium (PIERS)

作者： X. L. Shao T. Y. Hu L. Li Z. L. Xiao Y. J. Rong Nanjing University of Science and Technology Nanjing China Science and Technology on Near-Surface Detection Laboratory Wuxi China

ISBN: (纸本)9781665409889

Frequency diverse array (FDA) has been extensively studied due to its unique range-dependent characteristics. To obtain an enhanced transmit beampattern, the multi-carrier technique, which applies multiple carrier frequencies on each antenna element, has been employed in many FDA schemes. However, as the number of antenna elements increases, the computational complexity and cost of the FDA system using the multi-carrier technique also become higher. In order to alleviate this issue, a sparse multi-carrier FDA(MCFDA) beampattern synthesis algorithm is proposed in this paper. We first establish a cost function that minimizes the difference between the designed and desired radiation parameters. Then the modified genetic algorithm (MGA) is used to solve this global optimization problem since the cost function is nonlinear and has multiple local minima. Numerical simulation results demonstrate that the proposed algorithm can save about 50% of the antenna elements compared to the existing same aperture-sized full uniform FDA beampattern synthesis methods, while generating a dot-shaped beampattern with a slightly deteriorating sidelobe level.

关键词： Frequency synthesizers Costs Transmitting antennas Cost function Numerical simulation Frequency diversity Aperture antennas

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RCS Reduction For UAV Array

RCS Reduction For UAV Array

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Cross Strait Quad-Regional Radio science and Wireless technology Conference (CSRWTC)

作者： Lei Zhou Haosu Zhou Yizhao Wang Beichen Liu Zhenbin Lv Qi Tang Shanghai Spaceflight Electronic and Communication Equipment Research Institute ShangHai China Science and Technology on Near-Surface Detection Laboratory ShangHai China Nanjing University of Science and Technology NanJing China Science and Technology on Near-Surface Detection Laboratory WuXi CHina

ISBN: (数字)9781665432436

ISBN: (纸本)9781665432443

It is difficult to achieve the effect of raid target because of the large Radar Cross Section (RCS) of Unmanned Aerial Vehicle (UAV) group when carrying out military missions. This paper proposes a method to reduce RCS of UAV linear array. Based on the principle of array scattering pattern synthesis, this paper calculates the RCS of a linear array UAV group and optimizes the posture of the UAV through a multi-objective evolutionary algorithm so that the RCS of the UAV group is significantly reduced within the viewing angle. The simulation results show that the reasonable arrangement of UAVs significantly reduces the RCS of the group within the specified viewing angle range.

关键词： Wireless communication Radar cross-sections Azimuth Simulation Scattering Evolutionary computation Autonomous aerial vehicles

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A Practical Control Strategy for Magnetic Levitation System against Two Probes Failures

A Practical Control Strategy for Magnetic Levitation System ...

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第三十九届中国控制会议

作者： Jinhui Li Kai Ding Jianmei Sun Chi Wang Hongtao Zhao Huijie Zhu Science and Technology on Near-Surface Detection Laboratory Department of Precision Mechanical Engineering Shanghai University

This paper addresses the active control for magnetic levitation system against two probes failures, which degrades the stability of the levitation control, decreases the ride comfort near the rail joint. Firstly, a minimum interaction model containing vertical dynamics of electromagnets, cabin and traditional control scheme is developed. The output characteristics of probes near or under the typical joint are obtained by fitting experimental data. It shows that the maximum of the deviation values is up to11 mm, which should be attenuated effectively. Inspired by the probes' output characteristics and limited response range in the process of crossing the joint, a practical joint recognition method is explored. It shows that the joint can be identified *** a pair of complementary filters acting on acceleration and limited gap signal is developed to reconstruct the levitation gap signals. It shows that the deviations of the synthesized value are reduced substantially. After building the overall dynamic model with details, numerical simulations are carried out, and the results illustrating the improvement of stability and extended low speed range are provided.

关键词： maglev levitation control probes failures joint

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Design and Verification of a Dielectric Laser Accelerator Test System for Sub-Relativistic Electrons 10

Design and Verification of a Dielectric Laser Accelerator Te...

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Nano-optoelectronics and Micro/Nano-photonics X 2024

作者： Chen, Ke Li, Dandan Liu, Ziyang Yang, Chenyi Lu, Bingheng Yang, Yadong Wang, Qianqian School of Optics and Photonics Beijing Institute of Technology Beijing100081 China National Key Laboratory on Near-surface Detection Beijing10072 China Key Laboratory of Photonic Information Technology Ministry of Industry and Information Technology Beijing100081 China

ISBN: (纸本)9781510682160

Dielectric laser accelerators (DLAs) can achieve acceleration gradients that are 1 to 2 orders of magnitude higher than traditional radiofrequency (RF) accelerators. Due to the micrometer-scale dimensions of the DLA acceleration structure, on the one hand, high requirements are imposed on the quality of the electron beam and the alignment among the electron beam, driving laser, and DLA in experiments. On the other hand, although the DLA acceleration gradient is very high, the acceleration distance is insufficient, resulting in relatively small absolute energy gain for sub-relativistic electrons after DLA acceleration. These electrons are susceptible to interference from stray electromagnetic fields during propagation, posing significant challenges to the resolution and accuracy of sub-relativistic electron energy spectrum testing. Based on the principle of laser-driven grating-structure DLA for accelerating electron beams, this paper designs a complete test system, constructs electronic dynamics simulation models and magnetic field measurement electron energy spectrum simulation models for verification, designs a double-layer magnetic shunt to shield the interference of leakage magnetic fields on electrons in the simulation, considers factors such as the beam spot radius, divergence angle, and geomagnetic field intensity of the electron beam that conform to experimental conditions, and finally obtains simulated images of electron spots on the fluorescent screen after the electron beam is deflected by the magnetic field. The electron dynamics simulation results show that the electron beam achieves a maximum energy gain of 14.4401 keV over an acceleration length of 36 μm, with an acceleration gradient reaching 401.114 MeV/m. Based on the acceleration effect, a magnetic field of BB = 170 Gs is set, and an electron spot after deflection is obtained. The edges of the spots before and after acceleration are separated by Δd = 4.2889 mm, and the maximum energy gain measurem

关键词： Fluorescent screens

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Ship Tracking with Static Electric Field Based on Adaptive Progressive Update Extended Kalman Filter

Ship Tracking with Static Electric Field Based on Adaptive P...

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2018 2nd International Conference on Electronic Information technology and Computer Engineering (EITCE 2018)

作者： Shouwei HU Bing YAN Science and Technology on Near-Surface Detection Laboratory College of Weapon Engineering Naval University of Engineering

An adaptive progressive update extended Kalman filter is introduced for unknown noise in ship tracking using static electric field. The corresponding state space model is established;the algorithm is introduced, and the simulation is designed. The simulation results show that the adaptive algorithm can effectively improve the performance of the algorithm, when the noise covariance deviates from the real value;the finite number of noise covariance estimation is beneficial to the stability of the filter.

关键词： filter Ship Tracking with Static Electric Field Based on Adaptive Progressive Update Extended Kalman Filter Kalman

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3D object tracking with transformer

arXiv

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arXiv 2021年

作者： Cui, Yubo Fang, Zheng Shan, Jiayao Gu, Zuoxu Zhou, Sifan Northeastern University Shenyang China Science and Technology on Near-Surface Detection Laboratory Wuxi China

Feature fusion and similarity computation are two core problems in 3D object tracking, especially for object tracking using sparse and disordered point clouds. Feature fusion could make similarity computing more efficient by including target object information. However, most existing LiDAR-based approaches directly use the extracted point cloud feature to compute similarity while ignoring the attention changes of object regions during tracking. In this paper, we propose a feature fusion network based on transformer architecture. Benefiting from the self-attention mechanism, the transformer encoder captures the inter- and intra- relations among different regions of the point cloud. By using cross-attention, the transformer decoder fuses features and includes more target cues into the current point cloud feature to compute the region attentions, which makes the similarity computing more efficient. Based on this feature fusion network, we propose an end-to-end point cloud object tracking framework, a simple yet effective method for 3D object tracking using point clouds. Comprehensive experimental results on the KITTI dataset show that our method achieves new state-of-the-art performance. Code is available at: https://***/3bobo/lttr. © 2021, CC BY.

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Semantic Segmentation for Evaluation of Defects on Smartphone Screens 5th

Semantic Segmentation for Evaluation of Defects on Smartphon...

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5th International Conference on Cognitive Systems and Signal Processing, ICCSIP 2020

作者： Zhu, Huijie Shen, Zhuohao Yuan, Shenggui Chen, Fuliang Li, Jinhui Science and Technology on Near-Surface Detection Laboratory Wuxi214035 China Department of Automation Shanghai Jiao Tong University Shanghai200240 China School of Software Engineering Shanghai Jiao Tong University Shanghai200240 China

ISBN: (纸本)9789811623356

Smartphone recycling is a heated topic recently because of environmental and economical concerns. However, the limited recognition ability of naked eyes to find defects on phones impedes further growth of the second-hand markets. Related work for this problem focuses on detection and feature extraction, which can be tough because of the thin shapes of the defects and similar characteristics obstructing discrimination between scratches and cracks. In this paper, we propose an algorithm using semantic segmentation based on HRNet to build an effective model to evaluate defects of screens quickly and precisely. We improve the performance of the model by introducing the Lovász-Softmax loss function and data augmentation. Peripheral methods including subdivision and postprocessing are proposed to reduce misprediction on small scratches and enforce reliability in practice. We compare our model with other networks on mIoU and Kappa scores, concluding on an empirical basis. © 2021, Springer Nature Singapore Pte Ltd.

关键词： Semantic Segmentation

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