• Title/Summary/Keyword: RSOD

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Development of RSOD using optical phase modulator (광위상 변조기를 이용한 RSOD 개발)

  • Hwang, Dae-Seok;Lee, Young-Woo
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.43 no.11 s.353
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    • pp.14-18
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    • 2006
  • Optical interferometer is used for various optical measurement fields in optical metrology and biomedical measurements. In an optical interferometer, optical delay line has to change the optical path length of a reference arm to match with that of a sample in and it's speed was limited by reference arm movement speed. In this paper, we proposed an all-fibered RSODRapid Scanning-speed Optical Delay) without any mechanical movement, and we applied this system to optical interferometer. Experimental setup is consist of pulse laser source (center wavelength 1304nm, pulse width 30ps, repetition rate 10GHz), two phase modulators and dispersive shifted fiber. As experimental results, we obtain the maximum time delay of 11ps at 10MHz repetition rate, and it is easily tuneable the time delay by modulation frequency and modulation voltage.

Aircraft Recognition from Remote Sensing Images Based on Machine Vision

  • Chen, Lu;Zhou, Liming;Liu, Jinming
    • Journal of Information Processing Systems
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    • v.16 no.4
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    • pp.795-808
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    • 2020
  • Due to the poor evaluation indexes such as detection accuracy and recall rate when Yolov3 network detects aircraft in remote sensing images, in this paper, we propose a remote sensing image aircraft detection method based on machine vision. In order to improve the target detection effect, the Inception module was introduced into the Yolov3 network structure, and then the data set was cluster analyzed using the k-means algorithm. In order to obtain the best aircraft detection model, on the basis of our proposed method, we adjusted the network parameters in the pre-training model and improved the resolution of the input image. Finally, our method adopted multi-scale training model. In this paper, we used remote sensing aircraft dataset of RSOD-Dataset to do experiments, and finally proved that our method improved some evaluation indicators. The experiment of this paper proves that our method also has good detection and recognition ability in other ground objects.

A Handheld Probe Based Optical Coherence Tomography System for Diagnosis of Dental Calculus (치석 진단용 소형 프로브 기반 광간섭단층촬영 시스템)

  • Lee, Chang-Ho;Woo, Chai-Kyoung;Jung, Woong-Gyu;Kang, Hyun-Wook;Oh, Jung-Hwan;Kim, Jee-Hyun
    • Journal of Sensor Science and Technology
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    • v.21 no.3
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    • pp.217-222
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    • 2012
  • Optical coherence tomography(OCT) is a noninvasive optical imaging tool for biomedical applications. OCT can provide depth resolved two/three dimensional morphological images on biological samples. In this paper, we integrated an OCT system that was composed of an SLED(Superluminescent Light Emitting Diode, ${\lambda}_0$=1305 nm bandwith= 141 nm), a reference arm adopting a rapid scanning optical delay line(RSOD) to get high speed imaging, and a sample arm that used a micro electro mechanical systems(MEMS) scanning mirror. The sample arm contained a compact probe for imaging dental structures. The performance of the system was evaluated by imaging in-vivo human teeth with dental calculus, and the results indicated distinct appearance of dental calculus from enamel, gum or decayed teeth. The developed probe and system could successfully confirm the presence of dental calculus with a very high spatial resolution($6{\mu}m$).