• Title/Summary/Keyword: ${\gamma}$-Ray radiation

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The Study for Improved Efficiency of the Detection of Radiation Sources Distribution using Image Processing (영상처리기반 감마선 분포탐지 효율 개선에 관한 연구)

  • Hwang, Young-gwan;Lee, Nam-ho;Kim, Jong-yeol;Jeong, Sang-hun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.05a
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    • pp.780-781
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    • 2016
  • The stereo radiation detection system detects gamma ray source and measures the two dimensional distribution image based on the detection result. Then the system is implemented to measure the distance to the radiation source from the system in 3D space using stereo vision algorithm. In this paper, we reduced the time for a gamma-ray scan space detection through image processing algorithms. In addition, it combines radiation and visible light images. Then we conducted a study for improving the distribution of gamma-ray detection efficiency through the stereo calibration using a 3D visualization. As a result, we obtain an improved detection time by more than 30% and have acquired a visible image with a 3D monitor.

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Effects of Low Dose ${\gamma}$ Radiation on the Radiosensitivity of Soybean(Glycine max L.) Plant (저선량 ${\gamma}$선 조사가 대두 식물체의 방사선 감수성에 미치는 영향)

  • Kim, Jae-Sung;Chae, Sung-Ki;Back, Myung-Hwa;Kim, Dong-Hee
    • Korean Journal of Environmental Agriculture
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    • v.19 no.4
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    • pp.324-327
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    • 2000
  • Soybean (Glycine max L. cv. Hwangkeum) seeds were irradiated with the dose of $0{\sim}20$ Gy to investigate the effect of the low dose ${\gamma}-ray$ radiation on the early growth and resistance to subsequent high dose of radiation. Germination rate was not enhanced in the seeds irradiated with low dos ${\gamma}-ray$ but plant height and fresh weight increased in the low dose irradiation group. The optimal radiation dose for the growth increasing was 8 Gy in soybean plant. Growth inhibition of soybean plants by high dose radiation was noticeably reduced by pre-irradiation of low dose radiation, Resistance to subsequent high dose of radiation was effective in 8 Gy and 20 Gy irradiation group.

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Radio-sensitivity Analysis and Selection of Useful Mutants of Rape (Brassica napus L.) by Gamma Irradiation (방사선 처리에 의한 유채의 생육 및 감수성 조사)

  • Goh, Eun Jeong;Kim, Wook-Jin;Kim, Jin-Baek;Kim, Dong Sub;Kim, Sang Hoon;Kang, Si-Yong
    • Journal of Radiation Industry
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    • v.4 no.3
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    • pp.277-283
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    • 2010
  • Rape (Brassica napus L.) plants are one of the major oilseed crops. The main components of rapeseed are oil (35 to 47%) and protein (15 to 32%). For the biodiesel production, the development of a new variety of rape plant with high biomass and/or oleic acid contents is required. In order to determine the optimum dose of gamma-ray irradiation, the rape seeds of cvs. Hanra (Hr), Youngsan (Ys), Tammi (Tm), and Tamra (Tr) were irradiated with a 100~4,000 Gy dose range of gamma-rays. Considering the growth factors, the optimum doses were determined to be within the range of 600~1,000 Gy for the selection of useful mutant lines. Six-hundred and eighty-eight (688) $M_2$ mutant lines were obtained from 600~1,000 Gy gamma-ray-irradiated $M_1$ plants through selfing. The growth characteristics, leaf shape, early flowering, and flower color were all investigated. The selected mutant numbers of early flowering, leaf shape, and flower color were 34, 52, and 3 from the four cultivars, respectively. These mutant lines will be used for the development of a new variety of rape plant with high biomass and oleic acid contents.

Radiation mechanism of gamma-ray burst prompt emission

  • Uhm, Z. Lucas;Zhang, Bing
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.49.3-50
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    • 2015
  • Synchrotron radiation of relativistic electrons is an important radiation mechanism in many astrophysical sources. In the sources where the synchrotron cooling timescale is shorter than the dynamical timescale, electrons are cooled down below the minimum injection energy. It has been believed that such fast-cooling electrons have a power-law distribution in energy with an index -2, and their synchrotron radiation has a photon spectral index -1.5. On the other hand, in a transient expanding astrophysical source, such as a gamma-ray burst (GRB), the magnetic field strength in the emission region continuously decreases with radius. Here we study such a system, and find that in a certain parameter regime, the fast-cooling electrons can have a harder energy spectrum. We apply this new physical regime to GRBs, and suggest that the GRB prompt emission spectra whose low-energy photon spectral index has a typical value -1 could be due to synchrotron radiation in this moderately fast-cooling regime.

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Radiation Monitoring on a Fuel Handling Machine with Semiconductor Sensors (반도체센서를 이용한 핵연료교환기 피폭방사선량 모니터링)

  • 김승호;김양모;이남호
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.3
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    • pp.249-254
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    • 2004
  • The radiation dosage of nuclear fuel handling machine of PHWR type NPP during normal operation is measured using semiconductor detectors. In order to predict and mitigate the damage of main components in fuel handling machine, caused by high irradiation, the radiation dosage exerted to the components by neutron and gamma ray is measured independently during one time of the fuel exchange, which is used far estimating the radiation dosage for one year. This result can guarantee the safety and economical efficiency for determining the replacement time of the high cost main components in fuel handling machine.

Experimental Study on Physical Control of Nematodes Using The Ionizing Radiation (방사선 처리에 의한 선충 방제 효과)

  • Lee Jae-Kwang;Yoo Dae-Hyun;Lee Myun-Joo
    • Journal of Environmental Science International
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    • v.14 no.12
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    • pp.1113-1117
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    • 2005
  • Gamma-ray treatment was used to exterminate nematodes, which were harmful to agriculture When gamma-ray at the dose range of $5\~75$ kGy was irradaidated, nematodes were reduced by $40\~50\%$ When irradiated over 30 kGy, almost nematodes were non-mobile and fluorochromatic reactions showed that $60\;\~80\%$ of nematodes with non-mobility died after irradiation. The results of electron spin resonance spectroscopy suggested that radicals generated by radiolysis could damage to nematodes.

Study on the Thermal Properties of the Gamma-ray Irradiated EVA/MWCNT Nanocomposites

  • Lee, Kyoung-Yong;Kim, Ki-Yup;Hwang, In-Ra
    • Journal of Radiation Industry
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    • v.3 no.1
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    • pp.31-37
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    • 2009
  • This paper describes the preparation of manufacturing a new nanocomposite material, which involves adding a multi walled carbon nanotube (MWCNT) to improve thermal characteristics of poly (ethylene-co-vinyl acetate) (EVA). We irradiated the prepared nanocomposites with doses of 50 kGy, 100 kGy and 200 kGy at a dose rate of $5kGy\;hr^{-1}$ and examined their thermal stability, activation energy and crosslink level by using a thermogravimetric analyzer (TGA) and gel fraction experiments. TGA results indicated that the samples with a MWCNT had higher Derivative Thermo Gravimetry (DTG) 2nd peak temperatures than those without a MWCNT. And activation energy of the samples reduced as the absorption dose and the MWCNT content increased. Finally, the gel fraction increased rapidly up to 100 kGy as total absorption dose increased, and then the growth rate of all samples was slowly increased from 100 kGy.

Development of Three-Dimensional Gamma-ray Camera (방사선원 3차원 위치탐지를 위한 방사선 영상장치 개발)

  • Lee, Nam-Ho;Hwang, Young-Gwan;Park, Soon-Yong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.2
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    • pp.486-492
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    • 2015
  • Radiation source imaging system is essential for protecting of radiation leakage accidents and minimizing damages from the radioactive materials, and is expected to play an important role in the nuclear plant decommissioning area. In this study, the stereoscopic camera principle was applied to develop a new radiation imaging device technology that can extract the radiation three-dimensional position information. This radiation three-dimensional imaging device (K3-RIS) was designed as a compact structure consisting of a radiation sensor, a CCD camera, and a pan-tilt only. It features the acquisition of stereoscopic radiation images by position change control, high-resolution detection by continuous scan mode control, and stereoscopic image signal processing. The performance analysis test of K3-RIS was conducted for a gamma-ray source(Cs-137) in radiation calibration facility. The test result showed that a performance error with less than 3% regardless of distances of the objects.

Preparation and Characterization of Poly(vinyl alcohol) Hydrogel Contain Metronidazole by Irradiation (감마선을 이용한 Metronidazole이 함유된 Poly(vinyl alcohol) 하이드로겔 제조 및 특성)

  • Baik, Jae;Park, Jong-Seok;Jong, Jin-Oh;Jeong, Sung In;Gwon, Hui-Jeong;Ahn, Sung-Jun;Lim, Youn-Mook
    • Journal of Radiation Industry
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    • v.10 no.1
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    • pp.21-27
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    • 2016
  • Periodontitis is disease of damaged gum tissue that is not removed the plaque onto teeth. In case that the symptoms of disease get pain worse, it will have to extract tooth because of tumefy or bleeding at gums so treatment of drug was required to periodontitis. In this study, the hydrogel was prepared by including superior viscous, excellent elastic, and biocompatibility of Poly(vinyl alcohol, PVA) and antimicrobial drug of Metronidazole (MD). The 15 wt% PVA was dissolved in deionized water and then prepared PVA solution was irradiated using gamma-ray at 25 kGy ($10kGy\;hr^{-1}$). In addition, PVA hydrogel was immersed in each 0.1, 0.25 and 0.5 wt% MD solution using stirrer for 24 hr. The result of the gelation, 0.5 wt% MD loaded PVA hydrogel(76%) was lower than PVA hydrogel (88.2%). The swelling ration of 0.5 wt% MD loaded PVA hydrogel (294.8%) was higher than PVA hydrogel (105.2%). The compressive strength and thermal properties of MD loaded PVA hydrogel was gradually lower. The drug release test of 0.5 wt% MD loaded PVA hydrogel (61%) was higher than 0.1 wt% MD loaded PVA hydrogel (12%). Therefore, MD loaded PVA hygrogel may be a promising tool for periodontitis medicine by gamma-ray.

Growth Characteristics and Morphological Variation Analysis of Mutant Lines Derived from Gamma-ray and Chemical Mutagen Treatments in Rubus fructicosus L. (블랙베리(Rubus fructicosus L.) 돌연변이 유전자원의 생육특성과 형태학적 변이 분석)

  • Ryu, Jaihyunk;Kim, Dong Sub;Ha, Bo-Keun;Kim, Jin-Baek;Kim, Sang Hoon;Jeong, Il Yun;Jo, Han-Jik;Kim, Ee-Yup;Kang, Si-Yong
    • Journal of Radiation Industry
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    • v.6 no.3
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    • pp.257-265
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    • 2012
  • This study was carried out to evaluate growth, morphological characteristics, and sugar content among fifty six blackberry (Rubus fructicosus) genotypes derived from gamma-ray treatment (fifty two lines), MNU treatments (three lines), and cross breed R. fructicosus${\times}$R. parvifolius(one line). While 56 genotypes had similar stem diameter with origin variety, the most of mutants showed reduced leaf size. Also, they showed a wide range of variation in fruit size and one hundred fruit weight compared with origin variety. In fruit size and sugar content, two mutant lines showed large fruit sizes and ten mutant lines showed 20% higher sugar content than the original variety. In the correlation analysis, positive relationships were determined between sugar content and stem diameter, fruit length, leaf wide and fruit length/fruit wide ratio. However, leaf length/leaf wide ratio showed a negative correlation with sugar content. The results will be used as fundamental data for Rubus fructicosus breeding program.