• 한국수정란이식학회지
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• 제26권3호
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• pp.165-169
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• 2011

The present study investigated the physiological evaluation of cloned mini-pigs in a transportable isolator. Transportable isolator was designed and manufactured by our research team for transporting gnotobiotic pig. Until now, no previous reports are available regarding the physiological activities and harmful effects when pigs were transported in this isolator. Five cloned mini-pigs of 1~2 year (s) old female with a body weight between 80~90 kg were used. The effects of transportable isolator on stress-related hormone, adrenocorticotrophic hormone (ACTH) and cortisol levels, and heart rate were evaluated. In addition, it was also examined the effects of transportable isolator on blood chemistry factors (alanine aminotransferase: ALT, aspartate aminotransferase: AST, blood urea nitrogen: BUN, glucose, and creatinine). Blood was sampled just before the beginning of transport (T0), at the end of transport (30min after the transport; T1), and 30 min after the end of transport (T2). At the same time, heart rate was also evaluated. As a result, heart rate had no significant (p>0.05) differences at the various-time points of study (T0, T1, T2). However, heart rate was slightly higher than normal range in T1 and T2. The ACTH level was higher than normal range. Whereas, the cortisol level was lower than normal range. There were no statistical significant differences both ACTH and cortisol level between different time groups. Also, there were no significant differences in blood chemistry factors. Therefore, our present study shows that transportable isolator has no harmful effect on stress and physiological condition in cloned mini-pigs.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.83-84
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• 2002

For estimation of chain-matching phenomena between normal paraffin as a solvent and straight-chain fatty acid as an additive, the density measurement of n-dodecane, n-tetradecane and n-hexadecane were carried out at oil temperature 313K and pressure up to 1.3 GPa. Their solidification pressure were easily determined by the appearance of molecular crystal, abrupt volumetric contraction and generation of heat of solidification and showed minima under the matching condition. The bulk modulus K of molecular crystal was evaluated using phase diagram. The bulk modulus showed maxima under the each matching condition. The chain matching effect on the bulk modulus beyond the scope of the interfacial phenomena are confirmed.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 춘계학술논문발표회 논문집
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• pp.234-237
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• 2008

A direct numerical simulation (DNS) code suitable for the prediction of buoyant jet diffusion flames was developed in this study. The thermodynamic and transport properties were evaluated using CHEMKIN package to enhance the prediction performance of the developed DNS code. A two dimensional simulations were performed for the jet diffusion flames in normal and zero-gravity conditions where the Froude numbers are 5 and infinity, respectively. The simulated buoyant jet diffusion flame in normal gravity showed that the unsteady and dynamic motion although the reynolds number is low (400). It was identified that the flame in normal gravity flickered periodically. The periodic motion of the flame disappeared in zero-gravity condition. The dynamic motion of the buoyant jet diffusion flame could be well understood by comparing the flame structures obtained by the simulations of normal and zero-gravity conditions.

• Biomolecules & Therapeutics
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• 제24권1호
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• pp.94-98
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• 2016

The objective of the present study was to elucidate the effect of bisphosphonates, anti-osteoporosis agents, on glucose uptake in retinal capillary endothelial cells under normal and high glucose conditions. The change of glucose uptake by pre-treatment of bisphosphonates at the inner blood-retinal barrier (iBRB) was determined by measuring cellular uptake of $[^3H]3$-O-methyl glucose (3-OMG) using a conditionally immortalized rat retinal capillary endothelial cell line (TR-iBRB cells) under normal and high glucose conditions. $[^3H]3$-OMG uptake was inhibited by simultaneous treatment of unlabeled D-glucose and 3-OMG as well as glucose transport inhibitor, cytochalasin B. On the other hand, simultaneous treatment of alendronate or pamidronate had no significant inhibitory effect on $[^3H]3$-OMG uptake by TR-iBRB cells. Under high glucose condition of TR-iBRB cells, $[^3H]3$-OMG uptake was increased at 48 h. However, $[^3H]3$-OMG uptake was decreased significantly by pre-treatment of alendronate or pamidronate compared with the values for normal and high glucose conditions. Moreover, geranylgeraniol (GGOH), a mevalonate pathway intermediate, increased the uptake of $[^3H]3$-OMG reduced by bisphosphonates pre-treatment. But, pre-treatment of histamine did not show significant inhibition of $[^3H]3$-OMG uptake. The glucose uptake may be down regulated by inhibiting the mevalonate pathway with pre-treatment of bisphosphonates in TR-iBRB cells at high glucose condition.

• 방사성폐기물학회지
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• 제17권2호
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• pp.167-181
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• 2019

최근 국내에서 육상 및 해상을 통한 소외 정상운반 시 진동 및 충격하중에 대한 사용후핵연료의 건전성 평가 기술 개발이 수행되고 있다. 이와 관련된 국내 연구사례는 전무하여 기존에 진행된 또는 현재 수행중인 해외연구사례를 조사하여 국내 연구에 참고하고자 한다. 2000년 이전 과거 미국의 사용후핵연료의 정상운반 시 진동 및 충격하중 측정 관련 연구현황을 조사하였고 2009년부터 미국국립연구소 주관으로 실시한 단축가진시험, 콘크리트블럭 트럭운반시험, 다축가진시험에 대해서 조사하였으며 2017년 미국 SNL, 스페인의 ENSA, 한국이 공동으로 수행한 복합운반시험을 상세히 조사하였다. 시험 준비과정, 절차, 가속도 및 변형률 측정결과, 유한요소 및 다물체동역학 해석과정 등이 조사되었다. 각 시험 별로 측정된 변형률 자료를 바탕으로 사용후핵연료 피로곡선과 비교한 결과 손상을 일으키기에는 매우 미미한 정도의 변형률이 발생한다는 초기 결론을 얻었음을 확인하였다. 하지만 현재 결론은 일부 결과만을 검토한 예비 결론으로 상세한 검토가 현재 미국에서 진행 중이다. 미국에서 지금까지 수행한 사용후핵연료의 정상운반조건에서의 진동 및 충격하중 측정과 관련하여 조사된 내용은, 국내 운반환경에서 사용후핵연료의 정상운반시험을 수행할 때 참고할만한 유용한 자료라 판단된다.

• Nuclear Engineering and Technology
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• 제25권2호
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• pp.248-254
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• 1993

본 연구에서는 법규에서 규정하고 있는 주변온도 38$^{\circ}C$의 정상수송조건하에서 수송용기의 건식수송조건에 대한 열해석을 평가하였다. 수송용기는 1회에 PWR 핵연료집합체 4개를 운반할 수 있는 용량을 가지며, 설계기준 핵연료는 연소도 38,000 MWD/MTU, 냉각기간 3년을 기준으로 하였다. 건식수송조건에 대한 열해석을 평가하기 위하여 COBRA-SFS 전산코드를 이용하였다. 수송용기 내부 cavity에 공기, 질소 및 헬륨가스를 채우는 세가지 조건에 대한 해석을 수행하였으며, 최대 핵연료봉의 온도는 수송용기 내부 cavity가 공기인 경우에는 277$^{\circ}C$, 헬륨인 경우에는 226$^{\circ}C$로 계산되었다. 이 값은 건식수송조건에서 수송용기 내부에 장전된 PWR 핵연료집합체가 열적으로 건전성을 유지하기 위한 규정온도보다 낮은 것으로 나타났다.

• 방사성폐기물학회지
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• 제5권3호
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• pp.199-212
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• 2007

IP-2형 운반용기는 정상운반조건에서의 자유낙하시험 및 적층시험을 수행한 후에 운반내용물의 분산 및 유실이 없어야 하며 외부표면에서의 방사선량률이 20%이상 증가할 수 있는 차폐능력의 상실이 없어야 한다. 본 연구에서는 두꺼운 철판을 구조재로 사용하며 볼트체결방식의 뚜껑을 가진 IP-2형 운반용기에 대한 구조 안전성을 평가하기 위한 해석적인 방안을 제안하였다. 해석적인 방법을 통하여 원자력발전소에서 발생된 방사성폐기물 드럼을 폐기물 처리시설에서 임시저장고까지 운반하기 위한 두 종류의 IP-2형 방사성폐기물 운반용기에 대하여 자유낙하조건에서 운반내용물의 분산 및 유실과 차폐손실이 없음을 확인하였다. 자유낙하조건에서 운반내용물의 분산 및 유실을 평가하기 위하여 최대 볼트단면 평균응력값과 최대 뚜껑열림량을 볼트의 인장강도와 뚜껑부에 존재하는 단차와 비교 평가하였다. 또한 최대 차폐두께 감소량을 이용하여 차폐손실을 평가하였다. 자유낙하조건에 대한 동적충돌해석을 검증하고 구조 안전성을 시험적으로 평가하기 위하여 자유낙하시험을 다양한 방향으로 실시하였다. 자유낙하시험에서는 운반내용물의 분산 및 유실은 볼트체결방식의 뚜껑에서 볼트의 파손 및 플랜지의 변형 등을 검사하여 평가하였으며, 차폐손실은 초음파 두께 측정기를 이용한 차폐두께를 측정하여 평가하였다. 해석에 대한 검증을 위하여 시험에서 취득한 변형률과 가속도를 동일한 위치에서 얻어진 해석결과와 비교하였다. 해석결과는 시험결과에 비하여 보수적인 결과를 보여주므로 해석에서 입증한 IP-2형 방사성폐기물 운반용기의 안전성은 보수적인 결과이다. 마지막으로 유한요소해석을 통하여 적층조건에 대한 IP-2형 방사성폐기물 운반용기는 안전함을 입증하였다.

• Nuclear Engineering and Technology
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• 제30권5호
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• pp.462-469
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• 1998

A package to transport high-level radioactive materials is required to withstand normal transport and hypothetical accident conditions pursuant to the IAEA and domestic regulations. The package should maintain the structural safety not to release radioactive material in any condition. The structural safety of the package has been evaluated by tests using proto-type or scaled-down models, however, the method by analysis is gradually utilized due to recent advancement of computers and computer codes. In this paper, to evaluate the structural safety of a radioisotope package of the KAERI, the three dimensional impact analyses under 9m free drop and 1m puncture were performed with an explicit finite-element code, the LS-DYNA3D code. The maximum stress intensity on each part was calculated and the structural safety of the package was evaluated in accordance with the regulations.

• 한국환경과학회지
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• 제2권3호
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• pp.161-177
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• 1993

The Yellow Sand Events observed over the Korean peninsula during 22-24 April, 1993 were examined using the synoptic data and GMS visible image to identify the transport path of the Yellow Sand and the main factor governing the duration of the Yellow Sand phenomenon. The 850 hPa convergence chart and the 700 hPa trajectory analyses of the air mass laden with Yellow Sand particles suggested that the Yellow Sand particles observed over Korea were probably transported from the Gobi Desert and the Loess Plateau. The duration of the Yellow Sand Events was about 35-40 hours rather shorter than normal as the high pressure system centered near the Mongolia region moved rapidly toward the Yellow Sea, which drove away the Yellow Sand particles over the Korean peninsula toward the Japan Islands, furthermore the low-level stratification of the air mass over the Korean penishula showed the unstable atmospheric condition leading to atmospheric diffusion of the particles. The trajectory analyses and the GMS visible image indicated that the long-range transport of the air mass laden with the Yellow Sand particles of this case was more dependent on the 700 hPa air flow than on the 850 hPa air flow.

• 한국기계가공학회지
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• 제14권6호
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• pp.35-40
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• 2015

An IP-2 type container is used for the transport of low-level radioactive materials. An IP-2 type metal container was modeled and analyzed for the dropping conditions in normal transport conditions required by NSSC Notice 2014-50, "Regulations on the packaging and transport of radioactive materials." Structural analyses were performed by finite element method, and the acceptability was reviewed by comparing the results with technical standards and maximum allowable stresses of each material. Structural members of the container were modeled as 3D solid elements, and the possible dropping directions were considered in these analyses. Results show that maximum stresses, maximum deformed gaps in the cover, and maximum estimated thickness reduction in structural members were well below the allowable limits; thus, the structural integrity of the container was confirmed.