• Journal of Radiation Protection and Research
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• v.29 no.2
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• pp.97-104
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• 2004

MIRD-type Korean adult male phantom, 'KMIRD' was constructed to calculate Korean-specific dosimetric quantities for radiation protection consideration. The external shape of KMIRD was based on national physical standard data of Korean. KMIRD has thicket trunk than MIRD5 and arm models divided from trunk. The height and weight of the KMIRD are 171 cm and 63.8 kg. ICRP23 data were referred to constitute organs and tissues of KMIRD. However nine organs were constructed based on Korean reference data provided by Radiation Health Research Institute. In the present study, the MCNPX2.3 Monte Carlo transport code was combined with KMIRD to calculate dose conversion coefficients for photon in the energy range from 0.05 to 10 MeV. The simulated irradiation geometries are broad parallel photon beams in AP, PA, LLAT and RLAT direction. Absorbed dose conversion coefficients were compared with data calculated with MIRD5, MIRD-type phantom based on ICRP23 reference man. In some organs, the discrepancies between two phantoms amount up to nearly 30%. The effective doses conversion coefficients of KMIRD are lower than those of MIRD5. The dose discrepancies between two MIRD-type phantoms ate because of physical differences between Korean and Western, also geometric differences between two phantoms. KMIRD should be revised using the full set of Korean reference data of all organs. The developed MIRD-type Korean adult male phantom can be applied to dose assessment of internal exposure.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05b
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• pp.875-881
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• 1995

원자력 연구소는 국제원자력기구(IAEA/RCA) 주관하에 1990년부터 1993년 사이 3차에 걸쳐 실시한 개인선량계에 대한 국제상호비교에 참여하였다. 국제 상호비교에 참여하여 사용된 개인선량계는 방사선작업종사자에 대한 외부방사선으로부터 피폭관리를 위하여 기 사용중인 Taedyne Isotope 사의 PB-3타입의 열형광선량계이며 선량계판독용으로 Tdedyne 9150자동판독기를 사용하였다. 본 논문에는 3차에 걸쳐 국제상호비교결과를 요약하였으며 저 에너지의 엑스선에 경우를 제외하고 모든 조사방사선에 대해 0.78에서 1.07사이에 상대비율로 결과를 나타내었다. 또한 미국기준 ANSI Nl 3.11에 의해 성능을 시험한 결과 모든 조사방사선장에 대해서 허용기준 0.5이하를 나타내었다.

• Journal of the Korean Society of Radiology
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• v.9 no.2
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• pp.79-99
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• 2015

Participants of this study were students of radiology who were attending colleges or universities located in Daegu and Gyeongbuk. This researcher conducted a questionnaire survey of those students from Feb. 3rd to 21st, 2014. The findings of the study can be summarized as follows. 1. Concerning the knowledge of radiation exposure management, the respondents' scores were highest in two items, or 'Materials based on lead or concrete may shield X-rays' and 'The sexual gland is very sensitive to radiation' and lowest in the item which says' 'Occupational radiation exposure dose should not exceed 20mSv a year in average on a 5-year period basis'. 2. The participants' scores for the attitudes of radiation exposure management were higher in two items, or 'Health examination should be made regularly in relation to radiation exposure' and 'Those who work within the area of irradiation should wear protective clothes' and lowest in the item which says 'Radiation exposure dose should be regularly measured for the calibration of the radiation system'. 3. For the behaviors of radiation exposure management, the surveyed students showed highest scores in two items, or 'When irradiating the patient, the radiator should be behind the protective barrier(plate)' and 'It is needed to receive the education of radiation exposure management regularly' While, their score for a behavior described in the item saying 'Before using the radiation system, it is needed to check whether the machine works normally.

• Journal of Radiation Protection and Research
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• v.39 no.4
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• pp.213-217
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• 2014

Medical operations and diagnosis using interventional radiology techniques have been increased. The management and monitoring of occupational radiation exposure to the staff of interventional radiology become important, specially because they stand in close proximity to the patient. The operational radiation protection quantity, Hp(10) which can be obtained from personal dosimeter do not always represent the effective dose to the staff. So, in this study, to estimate the critical organ doses to the staff of interventional radiology, Monte Carlo calculations with mathematical human phantom and dose measurements with personal dosimeters were carried out for the major interventional radiology procedures using C-arm. Results showed that the values of Hp(10) measured by personal dosimeters were higher than critical organ doses which were calculated. And the calculated dose to thyroids was much higher than those of other critical organ doses. For the proper radiation protection of the medical staff of interventional radiology, additional radiation protection for thyroids as well as for whole body shielding like wearing a lead apron should be considered.

• Journal of Radiation Protection and Research
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• v.33 no.4
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• pp.151-160
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• 2008

In Korean nuclear power plants (NPPs), two thermoluminescent dosimeters (TLD) were provided to workers who work in an inhomogeneous radiation field; one on the chest and the other on the head. In this way, the effective dose for radiation workers at NPPs was determined by the high deep dose between two radiation dose from these TLDs. This represented a conservative method of evaluating the degree of exposure to radiation. In this study, to prevent the overestimation of the effective dose, field application experiments were implemented using two-dosimeter algorithms developed by several international institutes for the selection of an optimal algorithm. The algorithms used by the Canadian Ontario Power Generation (OPG) and American ANSI HPS N13.41, NCRP (55/50), NCRP (70/30), EPRI (NRC), Lakslumanan, and Kim (Texas A&M University) were extensively analyzed as two-dosimeter algorithms. In particular, three additional TLDs were provided to radiation workers who wore them on the head, chest, and back during maintenance periods, and the measured value were analyzed. The results found no significant differences among the calculated effective doses, apart from Lakshmanan's algorithm. Thus, this paper recommends the NCRP(55/50) algorithm as an optimal two-dosimeter algorithm in consideration of the solid technical background of NCRP and the convenience of radiation works. In addition, it was determined that a two-dosimeter is provided to a single task which is expected to produce a dose rate of more than 1 mSv/hr, a difference of dose rates depending on specific parts of the body of more than 30%, and an exposure dose of more than 2 mSv.

• Journal of Radiation Protection and Research
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• v.11 no.1
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• pp.57-64
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• 1986

This paper described an improved technical method required for proper evaluation of personnel exposures by means of the photographic dosimeter developed by KAERI in lower gamma or X-ray energy regions, with which response of the dosimeter varies significantly. With calibration of the dosimeter in the energy range from 30 to 300 keV, the beam spectrum was carefully selected and specified it adequately. The absorber combinations and absorber thickness used to obtain the specified X-ray spectra from a constant potential X-ray machine were determined theoretically and also experimentally. A correlation between the density and exposure for the four separate energies, such as $49\;keV_{eff},\;154\;keV_{eff}\;250\;keV_{eff}\;and\;662\;keV$, is experimentally determined. As a result, it can be directly evaluated the exposure from the measured response of dosimeter.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.487-492
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• 2007

최근 잦은 기상이변으로 인한 자연재해는 그 빈도와 강도가 점차 증가하고 있다. 이러한 기상이변은 결국, 극단적인 가뭄이 닥칠 가능성이 농후할 것이고, 만일 극단적인 가뭄상황이 도래할 경우 제한급수 또는 절수로 인한 일반인이 느끼는 피해정도는 매우 늘어날 것이다. 본 연구는 가뭄상황시 제한급수를 고려한 소비자의 지불의사를 알아보고자, 7대 특 광역시와 32개 가뭄상습지역에 거주하는 일반인을 대상으로 생활용수 수요패턴과 가뭄상황을 고려한 생활용수의 가치를 추정하였다. 조사결과, 수돗물 수질 관련에 대해서는 가뭄상습지역보다 7대광역시가 더 민감하였고, 수돗물 수량에 대해서는 가뭄상습지역이 더 민감한 것으로 나타났다, 지불의사 추정은 양분선택형과 개방형을 혼합하여 지불의사액을 설문하였고, Tobit모형을 이용하여 지불의사액을 추정하였다. 추정결과, 교육수준이 높을 수록, 가구수가 많을수록, 소득이 높을수록 지불의사가 높은 것으로 나타났다. 또한, 가뭄으로 인해 생활용수의 25% 제한시에는 약 2010원, 50% 제한시에는 2,395원의 추가적인 지불의사가 있는 것으로 추정되었다. 결국, 조사가구의 평균 수돗물 사용량과 절감량등을 추정하여 계산한 결과, 생활용수 25% 제한시 $1m^3$당 추가적인 지불의사 금액은 약 534원으로 추정된다. 지불의사가 기대했던 것보다 낮은 이유는 소비자가 그 정도의 가뭄을 경험하지 못한데서 오는 조세저항으로 여겨진다. 그러나 이 같은 결과는 가뭄을 회피하기 위해 소비자가 기꺼이 지불할 수 있는 비용은 현재의 물 값보다 훨씬 높다는 것을 의미한다. 알 수 있었다.수 없는 실제 방사선작업 환경에서의 선량평가 수행시, 본 논문에서 제시한 선량평가방법을 적용할 경우 계획된 피폭과 예상하지 못한 방사선장에 대한 피폭을 구분할 수 있어 보다 심도 있는 피폭선량평가 및 방사선관리가 가능할 것으로 판단된다.황산기(黃酸基)의 함량은 가장 적었다내고 있었고, in vivo에서는 복강(復腔)(i. p.) 투여(投與)에서는 $12.9{\sim}22.2%$. 경구(經口)(p.o.) 투여(投與)에서는 $11.2{\sim}21.6%$의 높은 활성(活性)을 나타내고 있었다. 단 peroxidase 활성(活性)은 복강(復腔)(i. p.) 투여(投與)에서는 $129.0{\sim}188.6%$, 경구(經口)(p. o.) 투여(投與)에서는 $111.4{\sim}139.6%$의 활성(活性)을 나타내고 있었다.rucic acid를 다량함유(多量含有)하고 있는 목포단교 12는 다른 두 품종(品種)에 비(比)하여 장쇄지방산에 속하는 eicoseuoic acid가 11.7%로 많이 함유(含有)되어 있었다. 그리고 3품종(品種) 모두 중성지질(中性脂質) 획분(劃分)의 지질(脂質)은 전체지방산(全體脂肪酸) 조성(組成)의 비(比)와 별다른 차이(差異)를 나타내지 않았다.수 있으나 본원에서 사용 중인 장비에서 극히 적은 MU의 사용이 현저한 선량적 오차를 유발하진 않는 것으로 사료되어진다. 그러나 정도 관리 시 그 오차를 확인하는 과정은 장비의 사용과 수명에 따라 지속적으로 관리되어져야 할 것이다.>로 평균

• Journal of Radiation Protection and Research
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• v.24 no.4
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• pp.205-213
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• 1999

Effective dose conversion coefficients from unit activity radionuclides contaminated on the ground surface were calculated by using MCNP4A rode and male/female anthropomorphic phantoms. The simulation calculations were made for 19 energy points in the range of 40 keV to 10 MeV. The effective doses E resulting from unit source intensity for different energy were compared to the effective dose equivalent $H_E$ of previous studies. Our E values are lower by 30% at low energy than the $H_E$ values given in the Federal Guidance Report of USEPA. The effective dose response functions derived by polynomial fitting of the energy-effective dose relationship are as follows: $f({\varepsilon})[fSv\;m^2]=\;0.0634\;+\;0.727{\varepsilon}-0.0520{\varepsilon}^2+0.00247{\varepsilon}^3,\;where\;{\varepsilon}$ is the gamma energy in MeV. Using the response function and the radionuclide decay data given in ICRP 38, the effective dose conversion coefficients for unit activity contamination on the ground surface were calculated with addition of the skin dose contribution of beta particles determined by use of the DOSEFACTOR code. The conversion coefficients for 90 important radionuclides were evaluated and tabulated. Comparison with the existing data showed that a significant underestimates could be resulted when the old conversion coefficients were used, especially for the nuclides emitting low energy photons or high energy beta particles.