• Title/Summary/Keyword: 플라스틱 광섬유

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Fabrication and Characterization of a One-dimensional Fiber-optic Dosimeter for Electron Beam Therapy Dosimetry (치료용 전자선 계측을 위한 1차원 광섬유 방사선량계의 제작 및 특성분석)

  • Jang, Kyoung-Won;Cho, Dong-Hyun;Shin, Sang-Hun;Yoo, Wook-Jae;Jun, Jae-Hun;Lee, Bong-Soo;Moon, Joo-Hyun;Park, Byung-Gi
    • Progress in Medical Physics
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    • v.19 no.4
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    • pp.285-290
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    • 2008
  • In this study, we have fabricated a one-dimensional fiber-optic dosimeter for electron beam therapy dosimetry. Each fiber-optic dosimeter has an organic scintillator with a plastic optical fiber and it is embedded and arrayed in the plastic phantom to measure one-dimensional high energy electron beam profile of clinical linear accelerator. The scintillating lights generated from each sensor probe are guided by plastic optical fibers to the multi-channel photodiode amplifier system. We have measured one-dimensional electron beam profiles in a PMMA phantom according to different field sizes and energies of electron beam. Also, the isodose and three-dimensional percent depth dose curves in a PMMA phantom are obtained using a one-dimensional fiber-optic dosimeter with different electron beam energies.

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Performance Analysis of OCDMA on Plastic Optical Fiber Access Network (플라스틱 광섬유를 사용한 통신망에서 OCDMA의 성능 분석)

  • Zhang, Ke;Suh, Hee-Jong
    • The Journal of the Korea institute of electronic communication sciences
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    • v.11 no.11
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    • pp.1083-1092
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    • 2016
  • In this paper, the performance of the optical code-division multiple access (OCDMA) technology on a plastic optical fiber (POF) access network, which had received much attention due to its low weight, large core diameter, flexibility, easy installation, and especially its high bandwidth, is analyzed. Recently, POF was a very attractive candidate for transmission media in an access network based on OCDMA technology. But the conventional OCDMA system only allows finite units to transmit and access simultaneously according to the number of channels which are restricted by BER, and so, in this paper, to resolve this problem a novel multi-priority reservation protocol is also proposed. By using this reservation scheme and a distributed arbitration algorithm, channel collision and destination conflict could be avoided. And this protocol can efficiently support the transmission of multimedia messages that require the different time-delay. The network throughput and average delay using various system parameters have been investigated by numerical analysis and simulation experiments. These results shows that the multi-priority reservation protocol in this POF access network based on OCDMA technology is valid and efficient.

Fabrication of Miniature Radiation Sensor Using Plastic Optical Fiber for Medical Usage (플라스틱 광섬유를 이용한 초소형 의료용 방사선 센서 제작)

  • Hwang, Young-Muk;Cho, Dong-Hyun;Cho, Hyo-Sung;Kim, Sin;Lee, Bong-Soo
    • Journal of radiological science and technology
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    • v.28 no.1
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    • pp.9-12
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    • 2005
  • In this study, film type radiation sensor tips are fabricated for remote sensing of X or g-ray with inorganic scintillators and plastic optical fiber. The visible range of light from the inorganic scintillator that is generated by X and g-ray is guided by the plastic optical fiber and is measured by optical detector and power-meter. It is expected that the fiber-optic radiation sensor which is possible to be developed based on this study is used for remote, fast and exact sensing of X or g-ray because of its characteristics such as very small size, light weight and no interference to electromagnetic fields.

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Development and comparison of two types MR-Compatible Photoplethysmograph Amplifiers (두 가지 타입의 MR-Compatible 맥파 측정 시스템 개발과 비교)

  • Lee, Gyeong-Sang;Yang, Jae-Ung;Choe, Mi-Hyeon;Lee, Su-Jeong;Jeon, Jae-Hun;Lee, Bong-Su;Jeong, Sun-Cheol
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2009.11a
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    • pp.148-151
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    • 2009
  • 본 연구에서는 광섬유를 이용하여 반사형과 투과형의 MR-Compatible Photoplethysmograph (PPG) 측정 시스템을 개발하고, 그 성능을 비교하고자 한다. 반사형 타입은 광섬유 다발의 끝단을 피부에 접촉 시킨 후 반사현상을 이용하여 PPG 신호를 측정하고, 투과형 타입은 광섬유 사이에 피부를 접촉시킨 후 투과현상을 이용하여 PPG 신호를 계측한다. PPG 측정 시스템은 광 신호를 검출하는 센서 부분, 근적외선 광 신호를 송수신하는 광케이블 부분, 신호 증폭 부분, 잡음 제거를 위한 필터부분으로 구성되어 있다. 반사형 및 투과형 PPG 신호의 SNR을 비교한 결과 반사형은 23.5dB이고 투과형은 22.2dB로 차이가 거의 없었다. 그러므로 실험 환경이나 목적에 따라 두 가지 타입 중 효율성이 좀 더 높은 것을 선택하여 사용할 수 있을 것이다.

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