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2023 International Congress on Ultrasonics, ICU Beijing 2023

作者： Li, Xuan Xiang, Yanxun Liu, Lishuai Xuan, Fu-Zhen Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power Engineering East China University of Science and Technology Shanghai200237 China

Aiming at the inherent dispersion characteristics of ultrasonic guided waves and the problems of gratings and side lobes in classical total focusing method (TFM) imaging algorithms, this paper proposes a full focus imaging algorithm based on reconstruct signals from phase information. Utilizing the numerical solution of the dispersion curve in the wavenumber domain, the time domain signal of Lamb wave is propagated backward to revise the changes in waveform shape caused by dispersion, and the flight time of the pulse-echo is eliminated simultaneously. The phase of pulse-echo after dispersion compensation should be consistent with the excitation signal. And the pulse-echo should have a large waveform correlation coefficient with the excitation signal. For each imaging point, dispersion compensation for all collected signals is respectively implemented so that the sign coherence factor (SCF) and the waveform correlation factor (WCF) between pulse-echo and excitation waveform can be extracted to reconstruct scattering signals. The reconstructed signals only contain information about the pulse-echo from defect. TFM imaging of the reconstructed signal can effectively suppress the grating side lobes of classical TFM imaging and improve the signal-to-noise ratio (SNR). © 2024 Institute of Physics Publishing. All rights reserved.

关键词： Dispersion compensation

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Counter-directional mixing of longitudinal guided waves to localize multiple micro-damages in a pipe

Counter-directional mixing of longitudinal guided waves to l...

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2023 International Congress on Ultrasonics, ICU Beijing 2023

作者： Gu, J.Y. Zhu, W.J. Xiang, Y.X. Xuan, F.Z. Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power Engineering East China University of Science and Technology Shanghai200237 China

Nonlinear guided wave has been considered as an effective means to detect early micro-damage in structures. In particular, the guided wave mixing technique has received great attention due to its ability to effectively isolate nonlinearity of measurement system and to localize micro-damage. Previous research mostly focuses on guided wave mixing in plate-like structures, and the research on guided wave mixing in pipes is very limited. Recent studies have been conducted on the co-directional mixing of guided waves in pipes. However, this mixing method is difficult to accurately localize multiple micro-damages because of the large mixing zone. In order to overcome these shortcomings, this study was carried out to investigate the counter-directional mixing of longitudinal guided waves in a pipe. Finite element simulations were performed on the counter-directional mixing of two primary guided waves in the pipe, and the generation of harmonic at the sum frequency was observed. The combined harmonic was used for the characterization and localization of two micro-damages in the pipe. The results show that by controlling the mixing zone of the two primary guided waves, micro-damage areas with an axial separation of 30mm can be effectively localized, which significantly improves the resolution of multiple micro-damages compared with the co-directional mixing method. Meanwhile, the relationship between the size of the mixing zone and the localization accuracy is discussed. This study provides a promising means for multiple micro-damages detection in pipes. © 2024 Institute of Physics Publishing. All rights reserved.

关键词： Guided electromagnetic wave propagation

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Weak value amplification via second-order correlated technique

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Chinese Physics B 2016年第2期25卷 58-61页

作者：崔挺黄靖正刘翔曾贵华 State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Key Laboratory on Navigation and Location-based Serviceand Center of Quantum Information Sensing and Processing Shanghai Jiao Tong University Shanghai Key Laboratory of Aerospace Intelligent Control Technology Shanghai Institute of Spaceflight Control Technology College of Information Science and Technology Northwest University

We propose a new framework combining weak measurement and second-order correlated technique. The theoretical analysis shows that weak value amplification （WVA） experiment can also be implemented by a second-order correlated system. We then build two-dimensional second-order correlated function patterns for achieving higher amplification factor and discuss the signal-to-noise ratio influence. Several advantages can be obtained by our proposal. For instance, detectors with high resolution are not necessary. Moreover, detectors with low saturation intensity are available in WVA setup. Finally, type-one technical noise can be effectively suppressed.

关键词： weak measurement two-dimensional second-order correlated function

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Single-atom Ni-N_(4) for enhanced electrochemical sensing

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Nano Research 2024年第8期17卷 7658-7664页

作者： Zhuhui Qin Bo Tang Guiru Zhang Chongqing Zhu Kun Jiang Bowei Zhang Fu-Zhen Xuan Shanghai Key Laboratory of Intelligent Sensing and Detection Technology East China University of Science and TechnologyShanghai 200237China Key Laboratory of Pressure Systems and Safety of Ministry of Education East China University of Science and TechnologyShanghai 200237China School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Theoretical and Computational Photochemistry Ministry of EducationCollege of ChemistryBeijing Normal UniversityBeijing 100875China Interdisciplinary Research Center School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Single-atom catalysts(SACs)attract widespread attention in heterogeneous catalysis due to their maximum atomic utilization efficiency and unique physical and chemical ***,their applications in chemical sensing keep huge potential but remain ***,a Ni-N_(4)-C SAC was synthesized for the trace detection of dopamine(DA)and uric acid(UA).The Ni-N_(4)-C SAC exhibited superior sensing performance compared to the Ni *** detection range for DA and UA were 0.05–75μM and 5–90μM with detection limits of 0.027 and 0.82μM,*** functional theory(DFT)computations indicate that Ni-N_(4)-C has a lower reaction barrier during electrochemical process,indicating that the atomic Ni sites possess higher intrinsic activity than Ni ***,DA and UA show strong potential dependency on the Ni-N_(4)-C catalyst,indicating its applicability for their concurrent *** work extends the application of SACs in chemical sensing.

关键词： single-atom catalysts chemical sensing dopamine uric acid

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Single-shot spatial-temporal-spectral complex amplitude imaging via wavelength-time multiplexing

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Advanced Photonics 2025年第02期 123-134页

作者： Yingming Xu Chengzhi Jin Liangze Pan Yu He Yunhua Yao Dalong Qi Cheng Liu Junhui Shi Zhenrong Sun Shian Zhang Jianqiang Zhu Research Center for Novel Computational Sensing and Intelligent Processing Zhejiang Lab Chinese Academy of Sciences Shanghai Institute of Optics and Fine Mechanics Key Laboratory of High Power Laser and Physics East China Normal University School of Physics and Electronic Science State Key Laboratory of Precision Spectroscopy South-Central Minzu University College of Electronics and Information Engineering China Jiliang University College of Optical and Electronic Technology

Single-shot ultrafast multidimensional optical imaging(UMOI) combines ultrahigh temporal resolution with multidimensional imaging capabilities in a snapshot, making it an essential tool for real-time detection and analysis of ultrafast scenes. However, current single-shot UMOI techniques cannot simultaneously capture the spatial-temporal-spectral complex amplitude information, hampering it from complete analyses of ultrafast *** address this issue, we propose a single-shot spatial-temporal-spectral complex amplitude imaging(STS-CAI)technique using wavelength and time multiplexing. By employing precise modulation of a broadband pulse via an encoding plate in coherent diffraction imaging and spatial-temporal shearing through a wide-open-slit streak camera, dual-mode multiplexing image reconstruction of wavelength and time is achieved, which significantly enhances the efficiency of information acquisition. Experimentally, a custom-built STS-CAI apparatus precisely measures the spatiotemporal characteristics of picosecond spatiotemporally chirped and spatial vortex pulses, respectively. STS-CAI demonstrates both ultrahigh temporal resolution and robust phase sensitivity. Prospectively, this technique is valuable for spatiotemporal coupling measurements of large-aperture ultrashort pulses and offers promising applications in both fundamental research and applied sciences.

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Robust template feature matching method using motion-constrained DCF designed for visual navigation in asteroid landing

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Astrodynamics 2023年第1期7卷 83-99页

作者： Yaqiong Wang Xiongfeng Yan Zhen Ye Huan Xie Shijie Liu Xiong Xu Xiaohua Tong College of Surveying and Geo-Informatics and Shanghai Key Laboratory of Space Mapping and Remote Sensing for Planetary EaplorationTongji UniversityShanghai 200092China Shanghai Institute of Intelligent Science and Technology Shanghai 200092China

A robust and eficient feature matching method is necessary for visual navigation in asteroid-landing *** on the visual navigation framework and motion characteristics of asteroids,a robust and efficient template feature matching method is proposed to adapt to feature distortion and scale change cases for visual navigation of *** proposed method is primarily based on a motion-constrained discriminative correlation filter(DCF).The prior information provided by the motion constraints between sequence images is used to provide a predicted search region for template feature ***,some specific template feature samples are generated using the motion constraints for correlation filter learning,which is beneficial for training a scale and feature distortion adaptive correlation filter for accurate feature ***,average peak-to-correlation energy(APCE)and jointly consistent measurements(JCMs)were used to eliminate false *** captured by the Touch And Go Camera System(TAGCAMS)of the Bennu asteroid were used to evaluate the performance of the proposed *** particular,both the robustness and accuracy of region matching and template center matching are *** qualitative and quantitative results illustrate the advancement of the proposed method in adapting to feature distortions and large-scale changes during spacecraft landing.

关键词： discriminative correlation filter(DCF) motion constraints feature distortion adaptive scale changes adaptive template feature matching

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Ultrahigh-sensitivity accelerometer enabled by EFPI and deflection amplification structure

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IEEE Transactions on Instrumentation and Measurement 2025年 74卷

作者： Ma, Junlong Chen, Yizheng Zhang, Qi Tang, Yan Chen, Ning Zhu, Xuran Zhang, Xiaobei Wang, Tingyun Shanghai University Key Laboratory of Specialty Fiber Optics and Optical Access Networks School of Communication and Information Engineering Shanghai200444 China China Electric Power Research Institute Laboratory of Electric Power Intelligent Sensing Technology and Application Beijing China

In this paper, an ultrahigh-sensitivity accelerometer incorporating an extrinsic Fabry-Perot interferometer (EFPI) and deflection amplification structure is proposed and experimentally demonstrated. The deflection amplification structure is constructed by a lever beam with cubic bead attached on the free end, and a buckled beam fixed at level beam midpoint. When exposed to acceleration, the lever beam vibrates, and force generated thanks to cubic bead gravity is greatly amplified and transferred to the connected buckled beam, which is finally converted into lateral displacement, thereby amplifying small displacement change at lever beam’s free end to one at the midpoint of buckled beam. And the amplified displacement is monitored by EFPI and full-spectrum demodulation algorithm. Theoretical and simulation analyses are applied to study the sensor response under vibration. Then the sensor is fabricated, and experiments are performed. Experimental results show that resonant frequency of the sensor is 368 Hz. In the flat frequency range of 10-200 Hz, the sensitivities at 100 Hz and 200 Hz are measured to be 11.118 μm/g and 8.075 μm/g, respectively. With the advantages of easy fabrication, ultrahigh-sensitivity and wide frequency bandwidth, the proposed accelerometer demonstrates great potential for structural health monitoring of power grid equipment. © 1963-2012 IEEE.

关键词： Structural health monitoring

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Utilizing wavelet packet decomposition to locate the damage of composite structures in strong-noise environment 7

Utilizing wavelet packet decomposition to locate the damage ...

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2024 7th International Conference on Mechanical, Electrical and Material Application, MEMA 2024

作者： Wang, Minjie Zhu, Wujun Xiang, Yanxun Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power Engineering East China University of Science and Technology Shanghai200237 China Key Laboratory of Modern Acoustics MOE Nanjing University Nanjing210023 China

This paper proposes an approach for damage localization in a strong noise environment based on wavelet packet decomposition. Experiments were conducted to locate damage in composite structures to verify the method. The signal was decomposed by a wavelet packet, and the damage information was identified through wavelet packet energy ratio deviation, defined as the damage factor. The proposed method effectively localizes the damage and directly captures the original signal without the need to preprocess the strong noise signals. Additionally, it bypasses the complex process of extracting reflected signals, demonstrating substantial potential for detecting and identifying composite damage in noisy environments. © Published under licence by IOP Publishing Ltd.

关键词： Wavelet decomposition

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Overcoming the Limits of Cross-Sensitivity:Pattern Recognition Methods for Chemiresistive Gas Sensor Array

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Nano-Micro Letters 2024年第12期16卷 285-341页

作者： Haixia Mei Jingyi Peng Tao Wang Tingting Zhou Hongran Zhao Tong Zhang Zhi Yang Key Lab Intelligent Rehabil&Barrier Free Disable(Ministry of Education) Changchun UniversityChangchun 130022People’s Republic of China Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237People’s Republic of China National Key Laboratory of Advanced Micro and Nano Manufacture Technology Department of Micro/Nano ElectronicsSchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012People’s Republic of China

As information acquisition terminals for artificial olfaction,chemiresistive gas sensors are often troubled by their cross-sensitivity,and reducing their cross-response to ambient gases has always been a difficult and important point in the gas sensing *** recognition based on sensor array is the most conspicuous way to overcome the cross-sensitivity of gas *** is crucial to choose an appropriate pattern recognition method for enhancing data analysis,reducing errors and improving system reliability,obtaining better classification or gas concentration prediction *** this review,we analyze the sensing mechanism of crosssensitivity for chemiresistive gas *** further examine the types,working principles,characteristics,and applicable gas detection range of pattern recognition algorithms utilized in gas-sensing ***,we report,summarize,and evaluate the outstanding and novel advancements in pattern recognition methods for gas *** the same time,this work showcases the recent advancements in utilizing these methods for gas identification,particularly within three crucial domains:ensuring food safety,monitoring the environment,and aiding in medical *** conclusion,this study anticipates future research prospects by considering the existing landscape and *** is hoped that this work will make a positive contribution towards mitigating cross-sensitivity in gas-sensitive devices and offer valuable insights for algorithm selection in gas recognition applications.

关键词： Pattern recognition Sensor array Chemiresistive gas sensor Cross-sensitivity Artificial olfactory

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Recent Advances in Fiber-Optic Sensors for the detection of Inorganic Acidic Gases

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Photonic Sensors 2024年第4期14卷 74-100页

作者： Lingnan KONG Yuanke GONG Xiaoyu ZHONG Yang LIU Bo WAN Quanhua XIE Yuanyuan HE Xiaoling PENG Haixing CHANG Dengjie ZHONG Huiling LIU Nianbing ZHONG Chongqing Key Laboratory of Optical Fiber Sensor and Photoelectric Detection Chongqing Key Laboratory of Modern Photoelectric Detection Technology and InstrumentsChongqing Engineering Research Center of Intelligent Optical Fiber Sensing TechnologyChongqing University of TechnologyChongqing 400054China Meishan San Su Shrine Museum Meishan 620010China School of Chemistry and Chemical Engineering Chongqing University of TechnologyChongqing 400054China College of Computing and Informatics Sungkyunkwan UniversitySeoul 03060South Korea

An acidic gas is an important basic chemical raw material used for synthesizing fertilizers,insecticides,explosives,dyes,and ***,inorganic acidic gases that leak into the air have harmful effects on the human health,infrastructure,and cultural ***,the demand for inorganic acidic gas sensors for air quality monitoring and management has continuously increased,enabling the development of various sensing *** them,fiber-optic sensors are promising for acidic gas detection because of their excellent in-situ measurement,resistance to corrosion,anti-electromagnetic interference,long service life,and smart *** particular,fiber-optic sensors have proven to be very useful for the in-situ detection and distributed monitoring of multiple gas ***,the sensitivity,selectivity,repeatability,and limits of detection of these sensors can be improved to achieve acceptable performance levels for practical *** this review,we introduce fiber-optic sensors based on structured optical fibers and fiber gratings for detecting H_(2)S,SO_(2),NO_(2),CO_(2),and N_(2)*** structures of the sensing regions,gas-sensitive materials,and measurement principles of these sensors are *** sensitivity,selectivity,limit of detection,and response time of the sensors are ***,the future of fiber-optic sensors for the detection of inorganic acidic gases is discussed.

关键词： Fiber-optic sensors structured optical fibers fiber gratings inorganic acidic gases measurement principles sensing performance

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