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2024 Photonics and Electromagnetics Research Symposium, PIERS 2024

作者： Lv, Yanfang Zhang, Lanjie Zhang, Yifan Zhang, Biao Key Laboratory of Information and Communication Systems Ministry of Information Industry Beijing Information Science and Technology University Beijing100101 China Key Laboratory of Modern Measurement and Control Technology Ministry of Education Beijing Information Science and Technology University Beijing100101 China

ISBN: (纸本)9798350375909

As an essential component of the earth system, precipitation plays a crucial role in the regional and global water cycle. This paper uses observations from the Fengyun-3D microwave humidity and temperature sounder and microwave radiation imager, as well as Integrated Multi-satellite Retrievals for GPM (IMERG), to establish a precipitation retrieval model based on the light gradient boosting model (LGBM). Using IMERG as the comparison data, the performance of precipitation identification with the LGBM-based precipitation retrieval model is as follows: accuracy is 0.9302, probability of detection is 0.7683, false alarm rate is 0.3529, and critical success index is 0.5414. The performance of precipitation estimation is also evaluated, with a correlation coefficient of 0.7536, a mean absolute error of 0.9119, and a mean squared error of 3.9506. In summary, this study achieves good performance in precipitation identification and estimation by the LGBM model. © 2024 IEEE.

关键词： Microwave acoustic devices

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In-Vehicle Network Injection Attacks Detection Based on Feature Selection and Classification

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Automotive Innovation 2024年第1期7卷 138-149页

作者： Haojie Ji Liyong Wang Hongmao Qin Yinghui Wang Junjie Zhang Biao Chen Key Laboratory of Modern Measurement and Control Technology Ministry of EducationBeijing Information Science and Technology UniversityBeijing 100192China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China School of Transportation Science and Engineering Beihang UniversityBeijing 100191China Hefei Innovation Research Institute Beihang UniversityHefei 230012China

Detecting abnormal data generated from cyberattacks has emerged as a crucial approach for identifying security threats within in-vehicle *** transmission of information through in-vehicle networks needs to follow specific data for-mats and communication protocols ***,statistical algorithms are employed to learn these variation rules and facilitate the identification of abnormal ***,the effectiveness of anomaly detection outcomes often falls short when confronted with highly deceptive in-vehicle network *** this study,seven representative classification algorithms are selected to detect common in-vehicle network attacks,and a comparative analysis is employed to identify the most suitable and favorable detection *** consideration of the communication protocol characteristics of in-vehicle networks,an optimal convolutional neural network(CNN)detection algorithm is proposed that uses data field characteristics and classifier selection,and its comprehensive performance is *** addition,the concept of Hamming distance between two adjacent packets within the in-vehicle network is introduced,enabling the proposal of an enhanced CNN algorithm that achieves robust detection of challenging-to-identify abnormal *** paper also presents the proposed CNN classifica-tion algorithm that effectively addresses the issue of high false negative rate(FNR)in abnormal data detection based on the timestamp feature of data *** experimental results validate the efficacy of the proposed abnormal data detection algorithm,highlighting its strong detection performance and its potential to provide an effective solution for safeguarding the security of in-vehicle network information.

关键词： Classification algorithm Anomaly detection In-vehicle network Feature extraction Injecting attack

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A high-speed structured light vision imaging and storage system based on Zynq SoC for 3D measurement 11

A high-speed structured light vision imaging and storage sys...

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Optoelectronic Imaging and Multimedia technology XI 2024

作者： Wan, Jimao Zhang, Qiankun Zhou, Zhehai Wang, Fusen Ban, Zhengjiang Key Laboratory of Modern Optoelectronic Measurement Technology in Mechanical Industry Beijing Information Science and Technology University Beijing100192 China Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instruments Beijing Information Science and Technology University Beijing100192 China

ISBN: (纸本)9781510682061

A trend in structured light 3D measurement systems is miniaturization. To address this trend, this paper presents a high-speed structured light vision imaging and storage system based on Xilinx Zynq-7000 SoC. The system employs a hardware-software co-design approach, with the hardware facilitating high-speed image capture and real-time display from a CMOS camera through programmable logic (PL), while the software manages camera configuration and image storage through the processing system (PS). In comparison to traditional FPGA-based image acquisition systems, the system proposed in this paper utilizes Zynq SoC based on ARM+FPGA architecture. By transitioning the SCCB configuration of the CMOS camera from FPGA to ARM processor control using Zynq, the system reduces hardware resources utilization and enhances camera configuration flexibility. Additionally, through the design of BMP image storage and PL-PS interrupt control programs, the system enables convenient camera calibration using stored images. Experimental results confirm the camera's ability to capture images at 1280×720 resolution with a frame rate of 30fps. Calibration of the CMOS camera using the system yields an average reprojection error of 0.09 pixels, meeting calibration accuracy requirements. This system serves as a foundation for embedded structured light 3D measurement systems. © 2024 SPIE.

关键词： CMOS integrated circuits

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A Q-switched, and mode-locked Er-doped fiber laser based on PbS-carbon nanotube saturable absorbers 15

A Q-switched, and mode-locked Er-doped fiber laser based on ...

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Advanced Lasers, High-Power Lasers, and Applications XV 2024

作者： Cao, Ying Zhao, Yue Chen, Guangwei Liao, Xiaochun Li, Hetian Zhong, Wen Yan, Pengyu Hu, Guoqing Zhao, Shuang Li, Huiyu Zhou, Zhehai Key Laboratory of Modern Optoelectronic Measurement Technology in Mechanical Industry Beijing Information Science and Technology University Beijing100192 China Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instruments Beijing Information Science and Technology University Beijing100192 China

ISBN: (纸本)9781510681927

Based on PbS quantum dots and single-walled carbon nanotube, we have successfully demonstrated a Er-doped fiber laser capable of switching between two different types of output pulses. By finely adjusting both the pump power and the states of polarization controller, flexible switchable Q-switched and mode-locked pulses can be achieved. At pump power of 29 mW, Q-switched pulses are obtained at a central wavelength of 1560.2 nm. When the pump power increases from 29 mW to 92 mW, the Q-switched rate varies from 25 kHz to 75.22 kHz. Accordingly, the output pulse energy rises from 3 nJ to 5.46 nJ, and the output power changes from 0.08 mW to 0.41 mW. When the pump power is set in the ranges of 92 mW to 107 mW, the fiber laser enters the transition region of Q-switching operation. In this region, evident Q-switched instability with large fluctuations is observed, which is independent of the polarization states. When the laser pump power exceeds 107 mW, the Q-switched pulse disappears, and mode-locked pulses are obtained by altering the state of the polarization controller. The central wavelength of the mode-locked pulses output spectrum is 1561.1 nm, and the corresponding 3 dB spectral bandwidth is 4.22 nm. Coupled Ginzburg-Landau equation are provided to reveal the underlying principles of the transition of these pulse trains. Our work provides a new prospect for achieving fiber lasers capable of flexibly switching output pulse types, further expanding their applications in fields such as laser microprocessing, optical communication and medical lasers. © 2024 SPIE.

关键词： Saturable absorbers

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Packaging technology for four channel 200 Gbit/s optical emission module based on PAM4 13

Packaging technology for four channel 200 Gbit/s optical emi...

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Optoelectronic Devices and Integration XIII 2024

作者： Wang, Fusen Zhou, Zhehai Wan, Jimao Ban, Zhengjiang Key Laboratory of Modern Optoelectronic Measurement Technology in Mechanical Industry Beijing Information Science and Technology University Beijing100192 China Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instruments Beijing Information Science and Technology University Beijing100192 China

ISBN: (纸本)9781510682009

A packaging scheme for optical transmission modules based on PAM4 with a data transmission rate of up to 200 Gbit/s is proposed to meet the design requirements of 200 Gbit/s PAM4 optical transceiver modules. Package integrates four PAM4 electrical/optical conversion ways internally, with a single channel data transmission rate of 50 Gbit/s. This article introduces the composition and technical difficulties of the 200 Gbit/s PAM4 optical emission module, and then models, simulates, and optimizes the 50 Gbit/s data transmission channel. Finally, the sample testing is completed. The test results show that the single channel PAM4 data rate of the sample can reach 50 Gbit/s, and the overall PAM4 data rate can reach 200 Gbit/s, meeting the design requirements of the optical transceiver module. © 2024 SPIE. All rights reserved.

关键词： Optical transceivers

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Switchable spectral sidebands based on modal interference effect in an Er-doped fiber laser 15

Switchable spectral sidebands based on modal interference ef...

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Advanced Lasers, High-Power Lasers, and Applications XV 2024

作者： Chen, Guangwei Zhao, Yue Cao, Ying Hu, Guoqing Li, Huiyu Zhao, Shuang Zhou, Zhehai Key Laboratory of Modern Optoelectronic Measurement Technology in Mechanical Industry Beijing Information Science and Technology University Beijing100192 China Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instruments Beijing Information Science and Technology University Beijing100192 China

ISBN: (纸本)9781510681927

Recently, the nonlinear multimodal interference-based all fiber saturable absorber has been the focus of attention on ultrafast fiber lasers, owing to its intriguing properties of versatility, high damage threshold and instantaneous response time. Although, challenges present in the technology, such as complex perturbation induced by quasi-degenerate modes in multimode fiber, it is presented as an effective solution to control the output characterization and study the nonlinear dynamics in fiber lasers. In this work, we experimentally and numerically demonstrate the spectral sidebands in a passively Er-doped fiber laser based on multimodal interference technique. Kelly-type and triangular-type sidebands are achieved, and can be switchable by changing the polarization states of cavity, which are asymmetric distribution on both sides of the output spectrum. When the polarization states are varied, a wide sideband is obtained, which the width of sideband can be tuned from 0.13 nm to 2.3 nm. Coupled complex Ginzburg-Landau equation are provided to reveal the underlying principles of the tunable features in sidebands. The results of numerical simulation show the relevance between filtering induced by modal interference, high-order dispersion, polarization modal dispersion and experimental results. Our work lays a foundation for understanding of nonlinear dynamics in mode locking fiber lasers based on multimodal interference effect, and provides a new way to generating versatile ultrafast source in engineering and scientific research. © 2024 SPIE.

关键词： Saturable absorbers

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Research on real-time online ranging system for wide-spectrum femtosecond laser interference based on frequency-domain peak detection method 11

Research on real-time online ranging system for wide-spectru...

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Optical Metrology and Inspection for Industrial Applications XI 2024

作者： Zhang, Zhiyong Chen, Li Zhao, Yue Qin, Ying Zhang, Xiang Cao, Yang Chen, Guangwei Hu, Guoqing Zhou, Zhehai Key Laboratory of Modern Optoelectronic Measurement Technology in Mechanical Industry Beijing Information Science and Technology University Beijing100192 China Key Laboratory of the Ministry of Education for Optoelectronic Measurement Technology and Instruments Beijing Information Science and Technology University Beijing100192 China

ISBN: (纸本)9781510682108

A real-time online ranging system is proposed using the frequency domain peak interval measurement method. By utilizing an NPR-locked, all-fiber, wide-spectrum erbium-doped femtosecond laser, a gain distribution with a center wavelength of 1560nm is obtained, with a repetition frequency of up to 14.54MHz, and then a femtosecond laser source with a spectral width of 38nm at -3dB can be obtained by adjusting its polarization state, which can improve ranging accuracy. By a combination of an upper computer system an all-fiber Michelson interferometer, real-time capture and processing of spectral interference data can be achieved, thereby realizing real-time acquisition of relative displacement distance. Experimental results show that within the coherence length, the measurable relative distance is around 2cm, and the measurement accuracy can reach 5μm. © 2024 SPIE.

关键词： Femtosecond lasers

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AN INVESTIGATION OF THE FACTORS AFFECTING THE SENSITIVITY OF A MEMS GYRO WITH FOUR SETS OF BIDIRECTIONAL THERMAL EXPANSION FLOWS 10

AN INVESTIGATION OF THE FACTORS AFFECTING THE SENSITIVITY OF...

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10th International Symposium on Test Automation and Instrumentation, ISTAI 2024

作者： Ma, Xuanlin Piao, Linhua Tong, Jiacheng Liu, Junyu Zhang, Yonghao Sun, Jiahao Beijing Key Laboratory of Sensors Beijing Information Science and Technology University Beijing100192 China Modern Measurement and Control Technology Ministry of Education Beijing Information Science and Technology University Beijing100192 China

ISBN: (纸本)9781837242672

In this paper, Factors affecting the sensitivity of a MEMS gyro with four sets of bi-directional thermal expansion flows, such as the duty cycle of the heating signal, in order to optimize the operating parameters and enhance performance, the upper chamber gas and other factors are investigated. The variation of the temperature field of the sensitive element is analysed and verified by calculations using COMSOL software, while a 3D model of the gyro is established. The optimized calculation results demonstrate that, under the conditions of the ideal heater frequency of 10 Hz, duty cycle of 60%, and power of 70 mW, the optimized MEMS thermal expansion flow gyroscope has a structural sensitivity of 23.5 mK/°/s when the input angular velocity is in the range of [-400%, 400%], using the upper chamber with a larger volume and Ar as the upper chamber's warming gas. The nonlinearity is 2.984%. The numerical analysis results extend the idea for the preparation and exploration of the same type of gyro in the future. © The Institution of Engineering & technology 2024.

关键词： Microchannels

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STUDY OF THE IMPACT RESISTANCE OF A SELF-BALANCING RESISTIVE THERMAL EXPANDING FLOW GYROSCOPE 10

STUDY OF THE IMPACT RESISTANCE OF A SELF-BALANCING RESISTIVE...

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10th International Symposium on Test Automation and Instrumentation, ISTAI 2024

作者： Tong, Jiacheng Piao, Linhua Ma, Xuanlin Liu, Junyu Zhang, Yonghao Sun, Jiahao Beijing Key Laboratory of Sensors Beijing Information Science & Technology University Beijing100192 China Modern Measurement and Control Technology Ministry of Education Beijing Information Science & Technology University Beijing100192 China

ISBN: (纸本)9781837242672

We propose thermal expansion flow gyroscopes with self-balancing resistance and study their impact resistance. In this paper, a thermal expansion flow gyro with self-balancing resistors is used as the research basis, aiming to improve the environmental adaptability of the gyro through technological innovation. The thermal expansion flow gyro contains an upper chamber, a lower chamber and a base layer, which contains four thermistors, two heating resistors and two balancing resistors. In order to improve the detection accuracy of the Wheatstone bridge, the balancing resistors and thermistors are fabricated using the same MEMS process, which ensures that the balancing resistors are highly consistent with the thermistors in terms of material, structure, and process, and achieves a high degree of matching and stability. Based on the above analysis, we carried out a finite element analysis of the impact resistance of the self-contained balancing resistor thermal expansion flow gyro. The experimental results show that the impact resistance of this thermal expansion flow gyro can reach 14,752 g when the load is applied in 0~10ms, which fully proves its high stability in harsh environments. The results of this study will provide a reference for subsequent gyro performance studies. © The Institution of Engineering & technology 2024.

关键词： Thermistors

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Smoking Behavior Detection in Park Security Based on Human key Points 5

Smoking Behavior Detection in Park Security Based on Human K...

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5th International Conference on Electronic Engineering and Informatics, ICEEI 2023

作者： Chen, Sai Zuo, Yunbo Hu, Huan Zheng, Yifan Li, Haowei Wang, Zhigang Key Laboratory of Modern Measurement and Control Technology Ministry of Education Beijing Information Science and Technology University Beijing100192 China China Mobile Park Construction and Development Company Beijing102206 China

ISBN: (纸本)9781643685021

Aiming at the potential security hazards caused by illegal smoking of some mobile personnel in the non-smoking area of the park, a method based on human body key points is proposed to detect smoking behavior. Firstly, the coordinate information of key points of the human body is extracted by OpenPose. Then, the distance ratio from the wrist to the nose and from the nose to the neck, as well as the angle between the upper arm and the forearm, are further calculated. The distance ratio is taken as the main basis and the angle is used as the auxiliary basis to distinguish smoking and non-smoking behaviors. Through the comparative analysis of the experimental results, it is found that this method can effectively identify the smoking posture of the characters in the self-collected smoking data. © 2024 The Authors.

关键词： Parks

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