• Title/Summary/Keyword: Radiation test

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A Study on the Selection of the Main Factors of Radiation Risk Index Model for assessing risk in Nondestructive Test workplace (방사선투과검사작업장 위험성 평가를 위한 방사선 위해도 지수 모델 주요인자 선정에 관한 연구)

  • Gwon, Da Yeong;Han, Ji young;Bae, Yu-Jung;Kim, Byeong-soo;Kim, Yongmin
    • Journal of the Korean Society of Radiology
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    • v.12 no.4
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    • pp.459-466
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    • 2018
  • Risk of radiation worker and radiation workplace are being mainly assessed by exposure dose. But, the radiation used in radiation workplace and the work environment are different. Because the nondestructive work environment varies depending on the work subject, the existence and nonexistence of shielding board, and so on. So, we need to consider the various factors in effective radiation protection aspect. We conducted a survey of radiation workers with over two years' experience in NDT workplace and heared the thoughts of experts. As a result, radiation source, exposure dose, current status of workplace management, workers with personel dosimetry problem and status of periodic regulatory inspection were chosen as main factors of radiation risk index model. Also, we primarily set weighting factors in order of importance based on questionnaires. Finally, we determined weighting factor for details of main factors through the professional advice. Therefore, we will be able to develop the radiation risk index model for assessing the risk of nondestructive test workplace based on main factors that are selected through this study.

The Study of Transient Radiation Effects on Commercial Electronic Devices (즉발감마선에 의한 상용전자소자의 피해현상분석 연구)

  • Oh, Seugn-Chan;Lee, Nam-Ho;Lee, Heung-Ho
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.10
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    • pp.1448-1453
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    • 2012
  • In this study, we carried out transient radiation test for identify failure situation by a transient radiation effect on operational amplifier devices. This experiments were carried out using a 60 MeV electron beam pulse of the LINAC(Linear Accelerator) facility in the Pohang Accelerator Laboratory. In this test, we has found that a serious failure as a burn-out effect due to overcurrent on the partial electronic devices.

The Implementation of Testing Board forSingle Event Upsets

  • Lho, Young-Hwan;Kim, Ki-Yup
    • International Journal of Aeronautical and Space Sciences
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    • v.5 no.2
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    • pp.28-34
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    • 2004
  • One of the major problem encountered in nuclear plants and satellites design isEMI (Electro-Magnetic Interference) and EMC (Electro-Magnetic Compatibility).Here, our focus is to implement the test board for checking SEU (Single EventUpsets); the effects of protons on the electronic system. The SEU results from thelevel change of stored information due to photon radiation and temperature in thespace environment. The impact of SEU on PLD (Programmable Logic Devices)technology is most apparent in ROM/SRAM/DRAM devices wherein the state ofstorage cell can be upset. In this paper, a simple and powerful test techniques issuggested, and the results are presented for the analysis and future reference. In ourexperiment, the proton radiation facilitv (having the energy of 50 MeV with a beamcurrent of 60 uA of cyclotron) available at KIRAMS (Korea Institute of RadiologicalMedical Sciences) has been applied on a commercially available SRAM manufacturedby Hynix Semiconductor Company.

A Study on the SEU in the SRAM to proton Irradiation

  • Lho, Young-Hwan;Park, Bo-Kyun;Kim, Bong-Sun
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.2295-2297
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    • 2003
  • The major problem encountered in satellite design is EMI (Electro-Magnetic Interference) and EMC (Electro-Magnetic Compatibility). Here, our focus is on the effects of protons on the electronic system. The SEU (Single Event Upset) results from the level change of stored information due to photon radiation and temperature in the space and the nuclear power plant environment. The impact of SEU on PLD (Programmable Logic Devices) technology is most apparent in ROM/SRAM/DRAM devices wherein the state of storage cell can be upset. In this paper, a simple and powerful test techniques is suggested, and the results are presented for the analysis and future reference. The test results are compared with that of JPL test report. In our experiment, the proton radiation facility available at KIRAMS (Korea Institute of Radiological Medical Sciences) has been applied on a commercially available SRAM manufactured by Hynix Semiconductor Company.

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Thermal Characteristics of Fire-Protection Foams Exposed to Radiant Heating (복사열에 노출된 소방용 폼 약제의 열적 특성 연구)

  • Kim, H.S.;Hwang, I.J.;Kim, Youn-J.
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.1570-1575
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    • 2004
  • In order to evaluate the performance of fire-fighting agents used to protect structures from heat and fire damages, the thermal characteristics of fire-protection foams are experimentally investigated. The current research focuses on the destruction of a fire-fighting foam subjected to heat radiation. A simple repeatable test for fire-protection foams subjected to fire radiation is developed. This test involves foam generation equipment, a fire source for heat generation, repeatable test procedures, and data acquisition techniques. Results of the experimental procedure indicated that each thermocouple within the foam responded in a similar manner and gradually to a temperature of $15^{\circ}C{\sim}20^{\circ}C$. At this point, each trace generally rises to a temperature of approximately $90^{\circ}C$. The temperature gradient in the foam as time passes increases with increased foam expansion ratio. In addition, it is determined that the temperature gradient along the foam for depth decreases with increased foam expansion ratio.

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Environmental Radiation Protection in Medical Institutions

  • Han, Eun-Ok;Dong, Kyung-Rae
    • Journal of Radiation Protection and Research
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    • v.35 no.3
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    • pp.91-95
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    • 2010
  • The study aimed to measure the levels of radiation protection for radiologists in medical institutions in three environmental categories (physical, administrative and social) and to establish a data base which can be used to increase awareness of environmental radiation protection in medical institutions within Korea. The study surveyed 10% of radiologists working in radiology departments in medical institutions which are supervised by the National Dose Registry overseen by the Korean Food and Drug Administration(KFDA). This study found that the level of environmental radiation protection was higher in the capital area and in larger hospitals. On the other hand, the study shows environmental radiation protection was lower in the Youngnam area and in clinics. Results from the questionnaires indicate the level of environmental radiation protection was higher when radiologists were given an individual dosimeter but lowest when the radiation protection apron quality test was conducted. Environmental radiation protection is an important factor for radiologists to conduct activities in a safe and protected environment. However, this study shows there are differences in the level of environmental radiation protection in medical institutions and location within Korea. In particular, the level of environmental radiation protection was lower in clinics, appropriate intervention strategies befitting these conditions are needed based on medical institution classification and location in order to improve the level of environmental protection.

Hybrid radiation technique of frequency-domain Rankine source method for prediction of ship motion at forward speed

  • Oh, Seunghoon;Kim, Booki
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.13 no.1
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    • pp.260-277
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    • 2021
  • The appropriate radiation conditions of ship motion problem with advancing speed in frequency domain are investigated from a theoretical and practical point of view. From extensive numerical experiments that have been conducted for evaluation of the relevant radiation conditions, a hybrid radiation technique is proposed in which the Sommerfeld radiation condition and the free surface damping are mixed. Based on the comparison with the results of the translating and pulsating Green function method, the optimal damping factor of the hybrid radiation technique is selected, and the observed limitations of the proposed hybrid radiation technique are discussed, along with its accuracy obtained from the numerical solutions. Comparative studies of the forward-speed seakeeping prediction methods available confirm that the results of applying the hybrid radiation technique are relatively similar to those obtained from the translating and pulsating Green function method. This confirmation is made in comparisons with the results of solely applying either the free surface damping, or the Sommerfeld radiation condition. By applying the proposed hybrid radiation technique, the wave patterns, hydrodynamic coefficients, and motion responses of the Wigley III hull are finally calculated, and compared with those of model tests. It is found that, in comparison with the model test results, the three-dimensional Rankine source method adopting the proposed hybrid radiation technique is more robust in terms of accuracy and numerical stability, as well as in obtaining the forward speed seakeeping solution.

A Study on knowledge, perception, self-efficacy, and performance on radiation protection among perioperative workers in terms of radiation protection (수술실 종사자의 방사선 노출에 대한 방사선 방어관련 지식, 인식도, 자기효능감 및 수행도에 관한 연구)

  • Kim, Bong-Hee;Kim, Hyo-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.5
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    • pp.343-354
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    • 2017
  • This study was designed to identify the knowledge, perception, self-efficacy, and performance on radiation protection among perioperative workers in terms of radiation protection. The factors affecting the performance of radiation protection were identified, and provide basic data for the development of an effective radiation protection education program. The sample was comprised of 166 perioperative workers who agreed to participate in this descriptive study. Data analysis was performed using the t-test, analysis of variance, Pearson's correlation, and multiple regression analyses on the SPSS 23.0 Program. The average time of radiation exposure was 3-4hoursThe radiation protection education experience was 11.4%. The average score of radiation protection knowledge was $8.61{\pm}2.51$; the perception was $4.59{\pm}0.64$; and the performance was $2.99{\pm}0.90$ There was a significant difference in the degree of radiation defense knowledge and performance among the general characteristics (p <001). Knowledge of radiation protection was correlated with the perception. The performance of radiation protection was correlated with the knowledge. The knowledge and perception of radiation protection behaviors should be increased to improve radiation protection performance. Therefore, it is important to promote the performance of radiation protection behaviors by improving the perioperative workers' knowledge of radiation protection through reinforcing radiation-related education.

Radiation effect on the corrosion of disposal canister materials

  • Minsoo Lee;Junhyuk Jang;Jin Seop Kim
    • Nuclear Engineering and Technology
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    • v.56 no.3
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    • pp.941-948
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    • 2024
  • The effects of radiation on the corrosion of canister materials were investigated for the reliable disposal of high-level radioactive waste. The test specimens were gamma-irradiated at a very low dose rate of approximately 0.1 Gy/h for six and twelve months. The copper and cast iron species were less corroded when irradiated. It is hypothesized that gamma rays suppress the formation of lower-enthalpy species like metal oxides and activate reductive reactions. In contrast, it was difficult to evaluate the effect of radiation on the corrosion of titanium and stainless steel.