• Title/Summary/Keyword: aeronautics

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Health monitoring of carbon fiber-reinforced polymer composites in γ-radiation environment using embedded fiber Bragg grating sensors

  • Jing Zhong;Feida Chen;Yuehao Rui;Yong Li;Xiaobin Tang
    • Nuclear Engineering and Technology
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    • v.55 no.8
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    • pp.3039-3045
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    • 2023

  • Fiber-reinforced polymer (FRP) composites are considered suitable candidates for structural materials of spacecrafts due to their excellent properties of high strength, light weight, and corrosion resistance. An online health monitoring method for FRP composites must be applied to space structures. However, the application of existing health monitoring methods to space structures is limited due to the harsh space environment. Here, carbon fiber-reinforced polymer (CFRP) composites embedded with fiber Bragg grating (FBG) sensors were prepared to explore the feasibility of strain monitoring using embedded FBG sensors in γ-radiation environment. The analysis of the influence of radiation on the strain monitoring demonstrated that the embedded FBG can be successfully applied to the health monitoring of FRP composites in radiation environment.

  • https://doi.org/10.1016/j.net.2023.04.028 인용 PDF

Performance of BMSC column with large eccentricity under natural exposure conditions

  • Ma, Haiyan;Zeng, Xiangchao;Yu, Hongfa;Yue, Peng;Zhu, Haiwei;Wu, Chengyou
    • Structural Engineering and Mechanics
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    • v.76 no.4
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    • pp.541-550
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    • 2020

  • As a new type of concrete material, basic magnesium sulfate cement concrete (BMSC) has the advantages, such as early strength, high strength, good toughness and crack resistance. However, it is unclear about the degradation of the mechanical properties of BMSC columns, which is exposed to the natural environment for several years. In order to apply this new concrete to practical engineering, six large-eccentricity compressive columns of BMSC were studied. The mechanical properties such as the crack propagation, failure morphology, lateral displacement and bearing capacity of BMSC column were studied. The results show that the degradation rate of ultimate load of BMSC column is from 6% to 7%. The degradation rate of the stiffness of the column is from 6% to 13%. With the increase of compressive strength of BMSC, the axial displacement and lateral displacement are gradually reduced. The calculation model of bearing capacity of the BMSC column under the large eccentric compression is proposed. This paper provides a reference for the application of BMSC columns in the civil engineering.

  • https://doi.org/10.12989/sem.2020.76.4.541 인용 KSCI

A Novel RFID Dynamic Testing Method Based on Optical Measurement

  • Zhenlu Liu;Xiaolei Yu;Lin Li;Weichun Zhang;Xiao Zhuang;Zhimin Zhao
    • Current Optics and Photonics
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    • v.8 no.2
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    • pp.127-137
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    • 2024

  • The distribution of tags is an important factor that affects the performance of radio-frequency identification (RFID). To study RFID performance, it is necessary to obtain RFID tags' coordinates. However, the positioning method of RFID technology has large errors, and is easily affected by the environment. Therefore, a new method using optical measurement is proposed to achieve RFID performance analysis. First, due to the possibility of blurring during image acquisition, the paper derives a new image prior to removing blurring. A nonlocal means-based method for image deconvolution is proposed. Experimental results show that the PSNR and SSIM indicators of our algorithm are better than those of a learning deep convolutional neural network and fast total variation. Second, an RFID dynamic testing system based on photoelectric sensing technology is designed. The reading distance of RFID and the three-dimensional coordinates of the tags are obtained. Finally, deep learning is used to model the RFID reading distance and tag distribution. The error is 3.02%, which is better than other algorithms such as a particle-swarm optimization back-propagation neural network, an extreme learning machine, and a deep neural network. The paper proposes the use of optical methods to measure and collect RFID data, and to analyze and predict RFID performance. This provides a new method for testing RFID performance.

  • https://doi.org/10.3807/COPP.2024.8.2.127 인용 PDF

FAA 61.15 모호성

  • Jeon, Jin-Hong;Kim, Chil-Yeong
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.5 no.1
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    • pp.97-100
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    • 1997

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