To ensure radiological safety margin in the transport and storage of spent nuclear fuel, it is crucial to perform source term and shielding analyses in advance from the perspective of conservation. When performing source term analysis on UO2 fuel, which is mostly used in commercial nuclear power plants, uranium and oxygen are basically considered to be the initial materials of the new fuel. However, the presence of impurities in the fuel and structural materials of the fuel assembly may influence the source term and shielding analyses. The impurities could be radioactive materials or the stable materials that are activated by irradiation during reactor power operation. As measuring the impurity concentration levels in the fuel and structural materials can be challenging, publicly available information on impurity concentration levels is used as a reference in this evaluation. To assess the effect of impurities, the results of the source term and shielding analyses were compared depending on whether the assumed impurity concentration is considered. For the shielding analysis, generic cask design data developed by KEPCO-E&C was utilized.

본 연구는 영산강수계 수질 특성을 파악하기 위하여 2001~2010년까지 영산강 본류 10개 지점의 수질측정자 료를 활용하여 총 18개 수질항목에 대하여 다변량분석법 을 이용하여 수질항목간의 상관관계 및 요인분석, 군집분 석을 수행하였다. 수질항목간 상관성은 BOD는 T-N, T-P 와 높은 양의 상관성을, Chl-a는 COD와 유의한 양의 상 관성을 보였다. 요인분석 결과 제1요인이 영양염류요인 (32.021%), 제2요인이 유기물 및 조류증식에 따른 물질대 사 요인(17.453%), 제3요인이 계절적 변동요인(14.775%), 제4요인이 미생물요인(10.951%)으로 추출되었다. 요인분 석 결과로부터 추출된 제1요인과 제2요인에 대한 군집 분석 결과, 오염도가 낮은 그룹, 광주천 및 하수처리수 방 류의 영향이 큰 오염도가 높은 그룹, 축산농가 및 농경지 등이 인근에 분포하는 그룹 등 3 그룹으로 분류되었다.

In this study, the feasibility of the biogas production by anaerobic digestion with agricultural byproducts, which are stems and leaves of hot pepper or sweet pepper from one of the agricultural villages in South Korea, was investigated. The physico-chemical compositions of the agricultural byproducts of hot and sweet pepper were analyzed and they were found to be favorable with anaerobic digestion. Theoretical methane potentials of the test materials were estimated as 393.1 L CH4/kg VS for hot pepper and 372.6 L CH4/kg VS for sweet pepper. Biochemical methane potentials were analyzed by Biochemical Methane Potential (BMP) test and those of hot pepper and sweet pepper were 107.9 and 193.4 L CH4/kg VS, respectively. Silage was chosen to be long-term storage method for biogasification. Biochemical methane potential of hot pepper was increased by silage storage, while that of sweet pepper was decreased. In the case of silage chopping size, ensiled material with 30 mm size showed higher biochemical methane potential than that with 3 mm size. Most of test materials showed higher biochemical methane potentials with microbial additives containing Bacillus Circulans than that containing Bacillus Subtilis.