• Journal of Radiation Protection and Research
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• v.30 no.3
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• pp.99-105
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• 2005

A model for evaluating radioactive contamination in the urban environment, named METRO-K, was developed as a basic step for accident consequence analysis in case of an accidental release. The three kind of radionuclides $(^{137}Cs,\;^{106}Ru,\;^{131}I)$ and the different chemical forms of iodine (particulate, organic and elemental forms) are considered in the model. The radioactive concentrations are evaluated for the five types of surface (roof, paved road, wall, lawn/soil, tree) as a function of time. Using the model, the contaminative impacts of the surfaces were intensively investigated with respect to with and without precipitation during the measurement periods of radionuclides in air. In addition, a practical application study was conducted using $^{137}Cs$ concentration in air and precipitation measured in an European country at the Chernobyl accident. As a result precipitation was an influential factor in surface contamination. The degree of contamination was strongly dependent on the types of radionuclide and surface. Precipitation was more influential in contamination of $^{137}Cs$ than that of $^{131}I$ (elemental form).

• Journal of Radiation Protection and Research
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• v.38 no.4
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• pp.208-213
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• 2013

The suitability of the site criteria is a basic requirement for securing safety of nuclear power plants. The suitability should be confirmed through the estimation of environmental radiation effects at the exclusion area boundary under the severe weather conditions. In this study, field tracer experiments over short range of 1 km radius under severe weather conditions were conducted at flat area in Daejeon. Severe weather conditions are represented with stable atmospheric condition and low wind speed. In general, the condition is appeared at clean night time with weak wind. The analysis of the measured distribution of the released tracer gas shows two big differences between the results of the past experiments conducted under the favorable weather conditions. One is the difficulty of finding the typical distribution of the released tracer gas with peak concentration in the downwind direction. The other one is the appearance of the contour of the concentration of tracer gas at several hundred meters even though the gas released at 10 m height over the ground.

• Parasites, Hosts and Diseases
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• v.34 no.1
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• pp.21-26
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• 1996

An experimental study was carried out to observe the effects of radiation on the infectivity of metacercariae of Gymnophalloines seoi to C3H mice. Oysters, the second intermediate host, were collected from an endemic area, and non-irradiated control, metacercaria-irradiation, and oyster-irradiation groups were prepared . One hundred metacercariae were infected orally to each mouse, and worm recovery rate was compared by groups at 7th day post-infection. In the metacercaria-irradiation group, the worm recovery rate was significantly reduced at radiation doses higher than 200 Gy, and the number of intrauterine eggs significantly reduced at doses over 50 Gy. In the oyster- irradiation group, 50 Gy significantly reduced both the worm recovery rate and number of uterine eggs. In the two groups, no worm was recovered at 1,000 Gy irradiation. Conclusively, irradiation of oysters with 200-1,000 Gy was effective to control infectivity of metacercariae to C3H mice, and could be adopted as a control measure for gymno-phalloidiasis.

• Quality Improvement in Health Care
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• v.15 no.2
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• pp.73-81
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• 2009

문제: 뇌졸중 환자를 돌보는 간호현장에서는 급성기 뇌졸중 환자의 증상악화에 대한 조기사정과 적절한 대처가 매우 중요한 문제이다. 그러나 임상현장에서는 이를 객관화하고 수치화하여 모든 의료진이 의사소통할 수 있는 유용한 도구를 사용하고 있지는 못하는 실정이다. 이러한 문제를 해결하기위해 NIHSS(National Institute of Health Stroke Scale)를 신경과 진료의사를 중심으로 활용하고 있지만 아직 간호현장에서는 보편적으로 사용하지 않고 있다. 이에 뇌졸중 환자 간호에 NIHSS를 활용하여 뇌졸중 증상악화의 조기사정과 빠른 대처로 궁극적으로는 뇌졸중 환자 간호의 질을 보다 향상시키기 위하여 본 활동이 시도되었다. 목적: 첫째, 간호사의 NIHSS 측정 신뢰도의 현수준을 점검하고 이를 향상시키기 위한 프로그램을 개발 적용한다. 둘째, 간호사가 급성기 뇌졸중환자에게 NIHSS 측정을 통하여 뇌졸중 악화를 얼마나 예측할 수 있는지 분석하고 이를 향상시킬 수 있는 방법을 모색한다. 셋째, 궁극적으로 급성기 뇌졸중 환자의 증상악화의 조기 발견과 치료를 위한 의료진의 올바른 대처지침을 마련하여 이를 적용한다. 의료기관: 경기도에 소재한 대학병원의 뇌졸중 집중치료실. 질 향상 활동: 첫째, 간호사의 NIHSS 측정 신뢰도 향상을 위해 "NIHSS 간호사 교육 프로그램"을 마련하였다. 둘째, NIHSS 측정을 통한 뇌졸중 악화 예측율 향상을 위하여 "뇌졸중 악화 발생 시 의사, 간호사 대처 활동 프로토콜"을 개발하고 추적 관찰하였다. 개선효과: NIHSS 측정 신뢰도는 질 향상 활동 전 89%에서 92%로 향상되었다. 그리고 간호사의 뇌졸중 악화 양성 예측율은 58.7%에서 87.1%로 향상되었다(참고 : 간호사의 뇌졸중 악화 음성 예측율 100% 유지). 즉 "NIHSS 간호사 교육 프로그램 활용", "뇌졸중 악화 발생 시 의사, 간호사 대처 활동 프로토콜"의 적용으로 뇌졸중의 조기 발견 및 치료가 가능하였고, 향후 환자 예후에 긍정적인 영향을 줄 수 있을 것이라 기대된다.

• Korean Journal of Microbiology
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• v.28 no.1
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• pp.13-18
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• 1990

A DNA sequence encoding the adr subtype preS2 region of hepatitis B virus envelope protein was fused to 5' end of lacZ gene yielding a plasmid pTSZ, in order to produce a preS2-$\beta$-galactosidase fusion protein. Serial deletions from 3' and 5' end of preS2 were constructed in plasmids, which were expressed and their antigenicities were examined with the monoclonal antibody H8. Deletions from amino and carboxy terminal to certain points did not affect the antigenicity, but the longer deletions destroyed the antigenicity. End points of deleted preS2 sequence were determined by DNA sequencing. As a result, each end of preS2 epitope was located in the region of amino acid residue 130-132 and 140-142, respectively. Residue 143 may be supplementary for antigenic epitope since the deletion from carboxy terminal to residue 143 revealed partial defect of antigenicity. In the interval of antigenic epitope the amino acid differences between adr and adw2 subtype occurred ar residue 130, 132, and 141. This result indicated that one or more of the three residues are responsible for the binding specificity of monoclonal antibody H8 to adr subtype preS2 fusion protein.

• Journal of Radiation Protection and Research
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• v.37 no.3
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• pp.116-122
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• 2012

A short-term atmospheric dispersion factor (${\chi}/Q$) is an essential element for radiological dose assessment following a hypothetical accidental releases of light-water nuclear power plants. The U. S. NRC developed PAVAN program to comply with the U. S. NRC's Regulatory Guide 1.145. Meteorological data is an essential element for atmospheric dispersion, and PAVAN uses a joint frequency distribution data, which represents the occurrence probability of wind speed and wind direction for atmospheric stability. Using the meteorological data measured at Kori and Wolsung sites for the last 5 years (from 2006 to 2010), a variety of joint frequency distribution data were prepared to evaluate ${\chi}/Q$ values with different wind speed classifications (U. S. NRC's recommendation and even distribution of occurrence probability) and periods of meteorological data to be analyzed (1 year, 2 year, 3 year, 4 year, 5 year). As a result, it was found that the influence of the wind speed classification on ${\chi}/Q$ values is little, while the influence of the periods of meteorological data to be analyzed is relatively significant, representing more than 1.5 times in the ratio of maximum to minimum values.

• Journal of Radiation Protection and Research
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• v.39 no.2
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• pp.70-80
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• 2014

The interpretation on the diffusion of radiation contaminants in air is usually to apply a Gaussian plume equation that obtains normal distributions in stable air flow conditions to draw a conservative conclusion. In this study, a numerical study using computational fluid dynamics methods was performed to interpret the air flow pattern and the diffusion of the radiation contaminants at the Wolseong nuclear power plants, and a more detailed solution can be obtained than the Gaussian plume equation, which is difficult to use to simulate complex terrains. The results show that a significant fluctuation of air flow in the terrain appears in the case of a northwester and southeaster because of the mountain located in the northwest and the sea located in the south-east. The northwesterly air flow shows the most unstable flow in the vertical direction when it passes over the terrain of mountain. The stable southeasterly air flow enters into the nuclear power plant from the sea, but it becomes unstable rapidly because of the interference by the building and the terrain. On the other hand, in the case of a northeaster and southwester, a small interruption of air flow is caused by the terrain and wake behind the buildings of nuclear power plants.

• Journal of Radiation Protection and Research
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• v.39 no.2
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• pp.89-95
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• 2014

In potential accident consequence assessments for the licensing approval of LWRs, the ground deposition of radionuclides released into the environment is not allowed into the models, as recommended in the U. S. Nuclear Regulatory Commission's regulatory guide. Meanwhile, it is allowed into the assessment models for the licensing approval of PHWRs with consideration of more detailed physical processes of radionuclides in the atmosphere. Under these backgrounds, importance of exposure dose by ground deposition was quantitatively evaluated and comprehensively discussed. For potential accidental releases of $^{137}Cs$ and $^{131}I$, total exposure doses were more conservative in case of without consideration of ground deposition than in case of with its consideration. It was because of that the depletion of air concentration resulting from ground deposition is more influential in the contribution to total exposure doses than additional doses from contaminated ground. The exposure doses by the inhalation of contaminated air showed the contribution of more than 90% in total exposure doses, depending on atmospheric stability, release period of radionuclides and distance from a release point. The exposure doses from contaminated ground showed less than 10% at most in contribution of total exposure doses. The ratios of total exposure doses in case of with consideration of deposition to without its consideration for $^{131}I$ were distinct than those for $^{137}Cs$. As the atmosphere is more stable, release duration of radionuclides is longer, distance from a release point is longer, it was more distinct.

• Journal of Radiation Protection and Research
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• v.36 no.3
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• pp.148-153
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• 2011

EMRAS-2 (Environmental Modelling for RAdiation Safety, Phase 2) is an international comparison program, which is organized by the International Atomic Energy Agency (IAEA), in order to harmonize the modelling of radionuclide behavior in the environment. To do so, the urban contamination working group within EMRAS-2 has designed the hypothetical scenarios for a specified urban area. In this study, the importance of contaminated surfaces composing an urban environment was analyzed in terms of dose rate using METRO-K, which has been developed to take a Korean urban environment into account. The contribution of contaminated surfaces to exposure dose rate showed distinctly a great difference as a function of specified locations and time following a hypothetical event. Moreover, it showed a distinct difference according to the existence of precipitation, and its intensity. Therefore, if an urban area is contaminated radioactively by any unexpected incidents such as an accident of nuclear power plants or an explosion of radioactive dispersion devices (RDDs), appropriate measures should be taken with consideration of the type of surface composing the contaminated environment in order to minimize not only radiation-induced health detriment but also economic and social impacts.

• Journal of The Korean Association For Science Education
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• v.34 no.6
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• pp.559-569
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• 2014

In this case study, we investigated teaching strategies of science teacher's teaching in science museum. Two secondary science teachers who completed a teacher training course on teaching in science museums participated in this study. We conducted interviews about their perceptions on teaching in science museum and their teaching plans before teaching. Then, we observed and recorded their teaching practices in the science museum throughout one semester, and collected all of the teaching materials. The interviews were also conducted after every lessons and at the end of the semester. For the analysis of teaching strategies, we used a framework that was revised from the framework for museum practice (FMP). The analysis of results revealed that the teachers understood the significance of planning the activities in a series of pre-visit, during-visit, and post-visit, so that they structured their teaching as continuous activities, not as an one-time event. However, they showed differences in the extent of connecting the activities with the national science curriculum according to their teaching objectives. In addition, there were differences in strategies such as promoting social interaction, evoking students' curiosity and interest, providing students with choices and control, and inducing engagement and challenge depending on each teacher's perceptions and experiences on teaching in science museum. These results suggest that science teacher education for the professional development of teaching in science museum should systematically provide knowledge and experiences on teaching strategies based on appropriate perceptions on teaching in science museum.