• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.12 no.2
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• pp.171-178
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• 2014

After the expiration of operating license of a plant, all infrastructures within the plant must be safely dismantled to the point that it no longer requires measures for radiation protection. Despite the fact that Kori 1 and Wolsong 1 are close to the expiration of their operating license, sufficient technologies for radiological characterization, decontamination and dismantling is still under development. The purpose of this study is to develop one of methods for radiological inventory assessment on measuring object by using direct measure of large component with In-Situ measurement technique. Radiological inventory was assessed by analyzing nuclide using portable gamma spectroscopy without dismantling reactor head, and the result of direct measurement was supplemented by performing indirect measurement. Radiochemical analysis were performed on surface contamination samples as well. During the study, radiological inventory of reactor vessel calculated expanding the result. Based on the result and the radioactivity variation of each radionuclides time frame for decommissioning can be decided. Thus, it is expected that during the decommissioning of plants, the result of this study will contribute to the reduction of radiation exposure to workers.

• Journal of radiological science and technology
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• v.30 no.3
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• pp.271-280
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• 2007

The objectives of this study were to identify the types of work values of radiological technology students and to verify the characteristics of them. The population of this study was the radiological technology students from 7 colleges randomly chosen in the whole country. data collected from 791 subjects were used. Types of work values were identified through the factor analysis and t-test between variables was used to determine the characteristics of the students. The research instrument used in this study was the Maryland Work Value Inventory(MWVI) designed by Meitus, R. The findings of this study were as follows ; 1. The types of work values of radiological technology students can be classified into 6 categories ; social contribution, achievement, capability, work interest, social status, economic reward. 2. Social contribution, achievement, capablity and work interest were classified as 'internal work values', while social status and economic reward as 'external work values'. 3. Work values of the radiological technology students were economic reward, social status, achievement, capablity, work interest, social contribution in order. 4. External work values of the radiological technology students got higher grade than internal work values.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2019.05a
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• pp.205-206
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• 2019

• Journal of the Korean Society of Radiology
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• v.15 no.4
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• pp.415-427
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• 2021

Korea Institute of Radiological and Medical Sciences has provided various beam irradiation services to researchers using a 50 MeV cyclotron beam line. In particular, since the neutron beam service uses the nuclear reaction between protons and beryllium, the possibility of activation of the irradiated sample increases by using a high current. In this study, MCNP 6.2 and FISPACT-II 4.0 were used to evaluate the possible activation during the 35 MeV 20 ㎂ neutron beam service, which is preferred by the researchers. As a result of the calculation, if the iron, copper, and tungsten samples were irradiated for more than 1 hour, long-lived radioisotopes were produced and their radioactivity exceeded the standard level for self-disposal. Under the conditions of 2 hours of daily irradiation, no activation occurred in the building materials, and the internal exposure of workers due to air activation inside the irradiation room was very insignificant. And when this air was discharged to environment, the radioactivity including this air was also satisfied the emission standard.

• Journal of the Korean Society of Radiology
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• v.2 no.3
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• pp.27-31
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• 2008

The radiation protection measures for the photoneutrons are one of the most important issue of radiation safety in high energy X-ray facilities. When the photoneutrons are released from the facility, the general public as well as occupational workers are exposed to unexpected radiations by neutron skyshine effect. In this study, the photoneutron inventory are calculated using monte carlo mothed, and the neutron skyshine dose rate is assessed using the inventory. A 9MeV X-ray cargo inspection facility is considered as a reference facility.

• Nuclear Engineering and Technology
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• v.52 no.6
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• pp.1148-1155
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• 2020

This work presents two different methods for quantifying and propagating the uncertainty associated with fuel composition at end of life for cask criticality calculations. The first approach, the computational approach uses parametric uncertainty including those associated with nuclear data, fuel geometry, material composition, and plant operation to perform forward depletion on Monte-Carlo sampled inputs. These uncertainties are based on experimental and prior experience in criticality safety. The second approach, the data-driven approach relies on using radiochemcial assay data to derive code bias information. The code bias data is used to perturb the isotopic inventory in the data-driven approach. For both approaches, the uncertainty in k_eff for the cask is propagated by performing forward criticality calculations on sampled inputs using the distributions obtained from each approach. It is found that the data driven approach yielded a higher uncertainty than the computational approach by about 500 pcm. An exploration is also done to see if considering correlation between isotopes at end of life affects k_eff uncertainty, and the results demonstrate an effect of about 100 pcm.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.233-234
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• 2004

최근 들어 국제 방사선 방호위원회(ICRP: International Commission on Radiological Protection)의 ICRP-60에서는 원전 작업종사자의 연간 허용 피폭량을 현행값인 5 rem보다 연 평가 2 rem으로 제한 운영토록 권고하고 있다. 이렇게 엄격해지는 방사선 관리규정에 능동적으로 대처할 수 있도록 새로운 방호차원에서 관련 계통 및 기기들의 방사선량을 낮출 수 있는 기술 개발이 절실한 실정이다. 각국의 원전에서는 방사능을 강구하고 있는 실정이다.(중략)

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.1
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• pp.113-121
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• 2021

A safety assessment of radioactive waste repositories is a mandatory requirement process because there are possible radiological hazards owing to radionuclide migration from radioactive waste to the biosphere. For a reliable safety assessment, it is important to establish a parameter database that reflects the site-specific characteristics of the disposal facility and repository site. From this perspective, solubility, a major geochemical parameter, has been chosen as an important parameter for modeling the migration behavior of radionuclides. The solubilities were derived for Am, Ni, Tc, and U, which were major radionuclides in this study, and on-site groundwater data reflecting the operational conditions of the Gyeongju low and intermediate level radioactive waste (LILW) repository were applied to reflect the site-specific characteristics. The radiation dose was derived by applying the solubility and radionuclide inventory data to the RESRAD-OFFSITE code, and sensitivity analysis of the dose according to the solubility variation was performed. As a result, owing to the low amount of radionuclide inventory, the dose variation was insignificant. The derived solubility can be used as the main input data for the safety assessment of the Gyeongju LILW repository in the future.

• Journal of the Korean Society of Radiology
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• v.5 no.6
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• pp.315-324
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• 2011

The purpose of this study was to use as basic data for the is systematic and efficient facility inventory of policeman and the riot police, conscripted policeman. First, the analysis was performed for the patient implementing the simple x-ray, CT, and MRI examination to the policeman and the riot police, conscripted policeman within the radiologic examination. As to the classification by disease, it classified into the partial body as the common disease and musculoskeletal system disease. As to the fixed quantity comparison of the policeman and the riot police, conscripted policeman the basic X-ray, CT, MRI examination by part average personnel was compared. As to the research result the riot police, conscripted policeman, the Lower extremity examination occupies the simple X-ray, CT, and MRI examination in comparison with the other part altogether much and particularly, the Knee examination ratio occupies much among the Lower extremity examination.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.spc
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• pp.75-87
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• 2020

The Korea Atomic Energy Research Institute (KAERI) has developed geological repository systems for the disposal of high-level wastes and spent nuclear fuels (SNFs) in South Korea. The purpose of the most recently developed system, the improved KAERI Reference Disposal System Plus (KRS⁺), is to dispose of all SNFs in Korea with improved disposal area efficiency. In this paper, a system-level safety assessment model for the KRS⁺ is presented with long-term assessment results. A system-level model is used to evaluate the overall performance of the disposal system rather than simulating a single component. Because a repository site in Korea has yet to be selected, a conceptual model is used to describe the proposed disposal system. Some uncertain parameters are incorporated into the model for the future site selection process. These parameters include options for a fractured pathway in a geosphere, parameters for radionuclide migration, and repository design dimensions. Two types of SNF, PULS7 from a pressurized water reactor and Canada Deuterium Uranium from a heavy water reactor, were selected as a reference inventory considering the future cumulative stock of SNFs in Korea. The highest peak radiological dose to a representative public was estimated to be 8.19×10^-4 mSv·yr^-1, primarily from ¹²⁹I. The proposed KRS⁺ design is expected to have a high safety margin that is on the order of two times lower than the dose limit criterion of 0.1 mSv·yr^-1.