• Title/Summary/Keyword: 감마형

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The Development of Beam Profiling System for the Analysis of Pulsed Gamma-ray Using the Electron Accelerator (전자빔가속기를 이용한 펄스감마선 출력특성 분석용 빔프로파일링 장치개발)

  • Hwang, Young-Gwan;Lee, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.12
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    • pp.2410-2416
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    • 2016
  • Recently, most countries in the world have pursued a denuclearization. So it has been of interest to increase to Nuclear weapon in such as North Korea's continued nuclear test. Pulsed gamma rays produced in the nuclear explosion and the space environment can give the big damage to the electronic device in a very short period of time. To confirm the extent of damage of these electronic devices, pulsed gamma irradiation facility that can occur in nuclear weapon or space environment are required. In this paper, we implemented the pulsed gamma-ray detection module and analyzed output of the irradiation test. We have experimented using an electron beam accelerator research facilities in Pohang Accelerator similar conditions to equip and Nuclear weapon. As a result, we confirmed that the pulsed gamma rays emitted by the gamma radiation and electron beam conversion device. The results of this paper will contribute to improve the reliability and accuracy of studies for utilizing pulsed gamma rays.

Study of Stirling Engine Design and Analysis (스털링엔진 설계 및 해석 연구)

  • Kim, Shin-Hyo;Cho, Dea-Kweon;Kim, Ui-Chang;Bae, Han-Na
    • Journal of Korea Ship Safrty Technology Authority
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    • s.38
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    • pp.2-11
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    • 2015
  • 최근 저탄소 녹색성장 및 그린에너지 개발 정책에 힘입어 외연기관의 일종으로 Stirling Engine에 대한 관심이 고조되고 있다. 스털링엔진은 크게 알파, 베타, 감마형의 3가지 방식으로 구분되어지며 그 중 감마타입 엔진의 설계가 용이하고 다양한 적용이 가능하다는 특징이 있음에도 실린더와 크랭크간의 접속거리 문제로 인하여 알파, 베타 타입에 비하여 용적을 크게 차지하는 문제가 있었다. 이를 해결하기 위한 방안으로 주로 알파형에 적용하는 Yoke crank를 적용하면 용적을 줄임과 동시에 실린더의 병렬화에도 유리하다. 금번 연구에서는 기존의 Ross Yoke crank 설계기법에서 나아가 감마형 스털링엔진의 Yoke crank 설계를 더욱 단순하고 효율적으로 적용할 수 있는 방법을 제시한다.

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Design of Gamma Camera with Diverging Collimator for Spatial Resolution Improvement (공간분해능 향상을 위한 확산형 콜리메이터 기반의 감마카메라 설계)

  • Lee, Seung-Jae;Jang, Yeongill;Baek, Cheol-Ha
    • Journal of the Korean Society of Radiology
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    • v.13 no.4
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    • pp.661-666
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    • 2019
  • Diverging collimators is used to obtain reduced images of an object, or to detect a wide filed-of-view (FOV) using a small gamma camera. In the gamma camera using the diverging collimators, the block scintillator, and the pixel scintillator array, gamma rays are obliquely incident on the scintillator surface when the source is located the periphery of the FOV. Therefore, the spatial resolution is reduced because it is obliquely detected in depth direction. In this study, we designed a novel system to improve the spatial resolution in the periphery of the FOV. Using a tapered crystal array to configure the scintillation pixels to coincide with the angle of the collimator's hole allows imaging to one scintillation pixel location, even if events occur to different depths. That is, even if is detected at various points in the diagonal direction, the gamma rays interact with one crystal pixel, so resolution does not degrade. The resolution of the block scintillator and the tapered crystal array was compared and evaluated through Geant4 Application for Tomographic Emission (GATE) simulation. The spatial resolution of the obtained image was 4.05 mm in the block scintillator and 2.97 mm in the tapered crystal array. There was a 26.67% spatial resolution improvement in the tapered crystal array compared to the block scintillation.

Effects of Gamma Irradiation on Array Type Fiber Bragg Grating Sensors (배열형 FBG 센서의 감마선 영향)

  • Kim, Jong-Yeol;Lee, Nam-Ho;Jung, Hyun-Kyu
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.10a
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    • pp.937-939
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    • 2016
  • In this study, we studied the gamma-radiation effect of fiber Bragg gratings (FBGs) manufactured by array sensors. The array FBGs were fabricated in a different Bragg wavelength using the same commercial Ge-doped fiber and exposed to gamma-radiation up to a dose of about 100 kGy at the dose rate of 113 Gy/min. It was analyzed radiation effects by measuring the radiation-induced change in the temperature sensitivity coefficient and Bragg wavelength shift after irradiation.

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Development of Gamma Camera System for Small Animal Imaging and Environmental Radiation Detection (소동물 영상화 및 환경 방사선 검출을 위한 감마카메라 개발)

  • Baek, Cheol-Ha
    • The Journal of the Korea Contents Association
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    • v.14 no.2
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    • pp.475-481
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    • 2014
  • The aim of this work was to develop the gamma camera system for small animal gamma imaging and environmental radiation monitoring imaging using a parallel hole collimator and pinhole collimator. The small gamma camera system consists of a CsI(Tl) scintillation crystal with 6 mm in thickness and $50{\times}50mm$ in area coupled with a Hamamatsu H8500C PSPMT, are resistive charge divider, pre-amplifiers, charge amplifiers, nuclear instrument modules (NIMs), an analog to digital converter and a computer for control and display. We have developed a radiation monitoring system composed of a combined pinhole gamma camera and a charge-coupled devices (CCD) camera. The results demonstrated that the parallel hole collimator and pinhole collimator gamma camera designed in this study could be utilized to perform small animal imaging and environmental radiation monitoring system. Consequently in this paper, we proved that our gamma detector system is reliable for a gamma camera which can be used as small animal imaging and environmental radiation monitoring system.