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Progress in Electromagnetic Research Symposium (PIERS)

作者： Ran Sun Fei Sun Yichao Liu Zeyu Zhang Chao Yang Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province College of Electronic Information and Optical Engineering Taiyuan University of Technology Taiyuan China

ISBN: (数字)9798350375909

ISBN: (纸本)9798350375916

In this study, double-physical-fields null medium, i.e., a subwavelength air channels surrounded by a carefully arranged metal plates, is utilized to design an electromagnetic-acoustic beam compressor capable of simultaneously compressing electromagnetic waves and acoustic waves. Numerical simulation results verify its ability to simultaneously produce the expected compression ratios for both electromagnetic waves and acoustic waves. Moreover, the compression ratio precisely matches the geometric size ratio of the input and output planes of the compressor. This work may have potential applications in electromagnetic-acoustic coupling systems and electromagnetic-acoustic processing/detection.

关键词： Couplings Electric potential Electromagnetic scattering Metals Numerical simulation Acoustic beams Electromagnetics

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A Dual-function Quasi-static Magnetic Device with Cloaking and Concentrating Functions Simultaneously

A Dual-function Quasi-static Magnetic Device with Cloaking a...

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Progress in Electromagnetic Research Symposium (PIERS)

作者： Hanchuan Chen Yichao Liu Fei Sun Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province College of Electronic Information and Optical Engineering Taiyuan University of Technology Taiyuan China

ISBN: (数字)9798350375909

ISBN: (纸本)9798350375916

In previous study, many single-function static/quasi-static magnetic devices, such as cloak and concentrator, have been designed base on transformation optics. However, few have explored devices capable of simultaneously generating two different functions on the static/quasi-static magnetic field. In this study, we propose a dual-function quasi-static magnetic device, which can create a concealed region and concentrated region for quasi-static magnetic field simultaneously. The dual-function quasi-static magnetic device is designed via twice extreme spatial stretching transformation and magnetic null medium, which can be realized by using arrays of superconductors and ferromagnetic materials in specific arrangement. The simulated results verify the performance of the proposed dual-function quasi-static magnetic device, which can simultaneously achieve cloaking and concentrating effect for the magnetic field from DC to 1000 Hz. The quasi-static magnetic field can be enhanced 9 times than the background magnetic field when the side lengths of the internal square pillar and external square pillar of the proposed structure are selected as a = 10 mm and b = 90 mm, respectively. Moreover, the concentrating ratio obtained from theoretical calculation fits well with the results obtained through numerical simulation. The dual-function quasi-static magnetic device designed in this study may have essential application in medical testing for special occasions.

关键词： Performance evaluation Magnetic devices Superconducting magnets Ferromagnetic materials Optics Numerical simulation Magnetic fields

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Pavement Disease Detection and Segmentation 23

Pavement Disease Detection and Segmentation

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Proceedings of the 2023 12th International Conference on Computing and Pattern Recognition

作者： Pengyu Liu Jiali Chen Shanji Chen Jing Yuan Faculty of Information Technology Beijing University of TechnologyBeijing Laboratory of Advanced Information NetworksBeijing Key Laboratory of Computational Intelligence and Intelligent System China Faculty of Physics and Electronic Information Engineering Qinghai Minzu University China

ISBN: (纸本)9798400707988

Pavement disease identification based on target detection and image segmentation is a common method in the maintenance of pavement diseases, which has great study value for the repair of road disease and road health status assessment. The study use pavement disease as the target, building segmention data set and detection data set which contains pothole, lateral crack, longitudinal crack and mesh crack. For the detection task, the pavement disease detection model is based on the improved YOLOv5, and the model’s mAP is 94.2%. For the segmentation task, pavement disease segmentation model is based on the improved U-Net, and the model’s mIOU is 94.4%.

关键词： U-Net YOLOv5 convolutional neural network pavement disease

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Nonvolatile Reconfigurable Phase-change-materials Integrated Silicon Photonics

Nonvolatile Reconfigurable Phase-change-materials Integrated...

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2024 Photonics and Electromagnetics Research Symposium, PIERS 2024

作者： Xu, Kai Wei, Maoliang Tang, Bo Li, Junying Yun, Yiting Lei, Kunhao Wu, Yingchun Li, Lan Lin, Hongtao Zhejiang University State Key Laboratory of Modern Optical Instrumentation Key Laboratory of Micro-Nano Electronics and Smart System of Zhejiang Province College of Information Science and Electronic Engineering Hangzhou China Institute of Microelectronics of the Chinese Academy of Sciences Beijing China University of Chinese Academy of Sciences Hangzhou Institute for Advanced Study Hangzhou China Westlake University Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province School of Engineering Hangzhou China Westlake Institute for Advanced Study Institute of Advanced Technology Hangzhou China

ISBN: (纸本)9798350375909

The emergence of integrated photonic technology provides an attractive solution of high speed, broad bandwidth and strong parallelism for large-scale information transmission and processing in interconnection, communication and computing. Reconfigurability is necessary for photonic processors to adapt varieties of application scenarios in the fields of data exchange, microwave photonics and neural networks. As yet, thermo-optical effect and carrier plasma dispersion effect are the most common phenomena for optical modulation. However, the volatility not only requires continuous power supply to maintain the devices' state, but also accompanies with serious thermal crosstalk induced by active regions. Hence, the nonvolatile methods that can reconfigure and fix on the current state for a long time after a single external excitation are considered as one of the significant technologies in the next generation of integrated photonics. Nonvolatile reconfiguration has been achieved through trapped-charge effect, bistable micro-electromechanical system (MEMS) with nano-latch mechanism and ferroelectric materials, which suffer from high loss, lower stability and complex process flow. Chalcogenide phase change materials (PCM) have become a promising method to realize compact and nonvolatile reconfigurable integrated photonic devices due to the high optical constant contrast between amorphous state and crystalline state, superiorly stable property and low temperature deposition possibility. Here, we developed a monolithic back-end-of-line integration technology of PCM in silicon photonics, supporting "Zero-change"heterogeneous integration platform at wafer scale. On this basis, nonvolatile integrated photonic devices with excellent performance have been fabricated. It lays a foundation for improving the energy efficiency and integration density of integrated photonic processors and suppressing thermal crosstalk between integrated photonic devices. © 2024 IEEE.

关键词： Silicon wafers

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A TRACK ASSOCIATION ALGORITHM BASED ON MOTION DYNAMICS FEATURES IN ENTOMOLOGICAL RADAR

A TRACK ASSOCIATION ALGORITHM BASED ON MOTION DYNAMICS FEATU...

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IET International Radar Conference 2023, IRC 2023

作者： Li, Biao Liu, Hanzhe Zhang, Tianran Cai, Jiong Wang, Rui The Radar Research Lab School of Information and Electronics Beijing Institute of Technology Beijing100081 China The Advanced Technology Research Institute Beijing Institute of Technology Jinan250300 China Beijing Key Laboratory of Embedded Real-time Information Processing Technology Beijing100081 China Beijing Institute of Electronic System Engineering Beijing100854 China

ISBN: (纸本)9781839539954

When tracking densely distributed targets such as insects, the traditional trajectory association algorithm exhibits poor correlation performance, leading to a decline in multi-target tracking efficiency. In this paper, based on the behavioral characteristics of insects gathering and co-orienting during aerial flight, a motion dynamic feature-assisted multi-target tracking method is proposed. Firstly, a three-dimensional biological distribution state matrix is constructed through spatial gridization. Then, a three-dimensional circular convolution is employed to estimate the target's motion dynamic feature, assisting in multi-target trajectory initialization. Finally, the improvement effect of the method on trajectory tracking accuracy is validated through simulations and migration insect data. © The Institution of engineering & Technology 2023.

关键词： Radar tracking

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Tunable uniform field enhancement in a subwavelength air pillar by photonic doping in epsilon-near-zero medium

arXiv

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arXiv 2024年

作者： Sun, Fei Shan, Jinyuan Liu, Yichao Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province College of Electronic Information and Optical Engineering Taiyuan University of Technology Taiyuan030024 China

In this study, a novel electric field compressor is proposed by doping a metal-air-metal pillar in epsilon-near-zero medium within a metallic waveguide, which effectively enhances the background electric fields in a sub-wavelength air pillar with high uniformity. The field enhancement factor can be analytically determined through theoretical derivations from Maxwell's equations, reaching its maximum value by appropriately selecting the size of the air pillar. Furthermore, the proposed compressor can achieve a tunable electric field enhancement effect within the deep sub-wavelength air pillar by adjusting the height of the air pillar through movement of two metal pillars inserted into the waveguide. Both theoretical analysis and numerical simulations are employed to validate the performance of the electric field compressor, which exhibits a wide range of tunable field enhancement effect (i.e., continuously adjustable enhancement factor between 20 and 800) with uniformity below 1.5 within the deep sub-wavelength air pillar (wherein the air volume is smaller than λ0/10 × λ0/10 × λ0/16). Finally, a practical model is proposed for the realization of the electric field compressor in the microwave range, where specially placed metal pillars and wires are incorporated into a rectangular metallic waveguide structure. The field enhancement and tunable effects of this practical model have been verified through simulations. Copyright © 2024, The Authors. All rights reserved.

关键词： Maxwell equations

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Behavior State Recognition of Complex Wingbeat Patterns Targets Based on Bi-LSTM

Behavior State Recognition of Complex Wingbeat Patterns Targ...

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IET International Radar Conference 2023, IRC 2023

作者： Wang, Lianjun Zhang, TianRan Li, Weidong Wang, Rui Hu, Cheng Radar Research Lab School of Information and Electronics Beijing Institute of Technology Beijing100081 China Advanced Technology Research Institute Beijing Institute of Technology Shandong Jinan250300 China Ministry of Education Beijing100081 China Beijing Institute of Electronic System Engineering Beijing100854 China

ISBN: (纸本)9781839539954

Radar serves as a crucial tool for observing airborne biological targets, with wingbeat frequency being a vital parameter for distinguishing between different species of organisms. The wingbeat patterns of airborne biological targets are diverse. To improve the extraction of wingbeat frequencies from radar signals, it is necessary to identify the behavioral states of different wingbeat patterns and eliminate signals that cannot be used for wingbeat extraction. This paper presents an intelligent recognition algorithm based on wingbeat pattern behavioral states. Firstly, Doppler frequency modeling is performed on wingbeat pattern targets, and then simulated data is input into a Bi-LSTM network for pattern recognition training. Finally, the algorithm's performance is validated using field radar measurements after performing short-time Fourier transformation on the measured data. The validation results based on radar experimental data indicate that this algorithm can effectively recognize wingbeat pattern behavioral states. © The Institution of engineering & Technology 2023.

关键词： Radar target recognition

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A reasoning diagram based method for fault diagnosis of railway point system

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High-Speed Railway 2023年第2期1卷 110-119页

作者： Feng Wang Yuan Cao Clive Roberts Tao Wen Lei Tan Shuai Su Tao Tang State Key Laboratory of Advanced Rail Autonomous Operation Beijing Jiaotong UniversityBeijing 100044China National Engineering Research Center of Rail Transportation Operation and Control System School of Electronic and Information EngineeringBeijing Jiaotong UniversityBeijing100044China Birmingham Centre for Railway Research and Education University of BirminghamBirmingham B152TTUK School of Electronic and Information Engineering Beijing Jiaotong UniversitBeijing 100044China Fronters Science Center or Smart High-speed Raiway Systm Beijing Jiotong Univers Beijing 00044China

Railway Point system(RPS)is an important infrastructure in railway industry and its faults may have significant impacts on the safety and efficiency of train *** the fault diagnosis of RPS,most existing methods assume that sufficient samples of each failure mode are available,which may be unrealistic,especially for those modes of low occurrence frequency but with high *** address this issue,this work proposes a novel fault diagnosis method that only requires the power signals generated under normal RPS operations in the training ***,the failure modes of RPS are distinguished through constructing a reasoning diagram,whose nodes are either binary logic problems or those that can be decomposed into the problems of the binary ***,an unsupervised method for the signal segmentation and a fault detection method are combined to make decisions for each binary logic *** on the results of decisions,the diagnostic rules are established to identify the failure ***,the data collected from multiple real-world RPSs are used for validation and the results demonstrate that the proposed method outperforms the benchmark in identifying the faults of RPSs.

关键词： Railway point system Fault diagnosis Reasoning diagram Segmentation Detection method

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Broadband planar electromagnetic hyper-lens with uniform magnification in air

arXiv

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arXiv 2024年

作者： Sun, Ran Sun, Fei Chen, Hanchuan Liu, Yichao Wang, Qi Key Lab of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province College of Electronic Information and Optical Engineering Taiyuan University of Technology Taiyuan030024 China

A planar hyper-lens, capable of creating sub-wavelength imaging for broadband electromagnetic wave, is designed based on electromagnetic null medium. Subsequently, a scheme for the implementation of the proposed hyper-lens is given by using well-designed flexural metal plates, which function as the reduced electromagnetic null medium for TM-polarized microwaves. Both simulated and measured results verify that the hyper-lens designed with flexural metal plates can achieve super-resolution imaging for microwave at operating wavelength (λ0=3cm) with a resolution of 0.25λ0 and a uniform magnification of about 5. Moreover, the designed hyper-lens ensures that both the object and image surfaces are planes, and simultaneously provides a uniform magnification for objects in different positions. Additionally, the proposed hyper-lens offers a broadband superresolution imaging capabilities, achieving good super-resolution imaging effects for microwave frequencies ranging from 8.5 to 11 GHz. The proposed hyper-lens may find applications in high precision imaging, detection, and sensing. Copyright © 2024, The Authors. All rights reserved.

关键词： Optical resolving power

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Elastic Collision Based-Interactive Path Planning system for Vascular Intervention Robots

Elastic Collision Based-Interactive Path Planning System for...

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International Conference on Biomimetic Intelligence and Robotics & Medical Robotics Forum, ICBIR+MRF 2024

作者： Cao, Sheng Guo, Shuxiang Guo, Jian Wang, Jian Wang, Bin Ding, Mingchao Aerospace Center Hospital The Key Laboratory of Convergence Medical Engineering System and Healthcare Technology School of Life Science Ministry of Industry and Information Technology Beijing Institute of Technology Beijing100081 China Shenzhen Institute of Advanced Biomedical Robot Company Limited Guangdong Province Shenzhen518000 China Department of Electronic and Electrical Engineering Southern University of Science and Technology Guangdong Shenzhen518055 China

As population aging intensifies, the incidence of cardiovascular and cerebrovascular diseases has continued to rise. Vascular interventional surgery, known for its minimal trauma, rapid recovery, and clear effectiveness, requires doctors to perform procedures in radiation environments while wearing lead aprons. The advent of vascular intervention robots has provided a system-level solution to protect doctors from radiation and enhance outcomes. Currently, preoperative path planning for these robots predominantly relies on automatically generated paths, calculated by setting constraints and minimizing costs. However, this method lacks incorporation of physicians' expertise and consideration of elastic collision. Therefore, this study has designed an interactive path planning system for vascular intervention robot based on elastic collision. By establishing a simulation environment, doctors can use a manipulator to control virtual catheters and guidewires. While considering deformations, they maneuver the guidewire to the target position and record the current motion trajectory to guide the procedure in actual surgeries. Experimental tests have been conducted, confirming the system's effectiveness and feasibility. © 2024 The Authors.

关键词： Robot programming

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