• Nuclear Engineering and Technology
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• 제21권3호
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• pp.186-192
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• 1989

14$\times$14형 교체노심용 핵연료집합체 상단고정체 설계의 일환으로 핵연료집합체 운송 및 취급시의 하중조건하에서 여러 상단고정체 구조모델들에 대한 구조해석을 ANSYS code를 사용하여 수행하였다. 해석 모델에서는 3차원 등매개변수(isoparametric) 요소를 사용하였으며 설계조건들을 위배하지 않으면서 Adapter plate에 있는 구멍들의 배치를 조정하는 한편 Adapter plate에 부착되는 두름판(Enclosure)의 부착 방법을 개선함으로서 상단고정체의 구조적 강도를 증가시켰다. 이러한 개념들은 14$\times$14 교체노심용 핵연료 설계에 채택되었다.

• 한국안전학회지
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• 제14권3호
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• pp.3-11
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• 1999

The atomic fuel rods between top and bottom end pieces of reactor need to be extended for high combustion rate of future-type fuel to increase the irradiation in the axial direction. For allowing axial extension of the fuel rods, the space between top and bottom end pieces should be expanded. Thus the thickness reduction of the flow plate is necessary. This study was carried out the mechanical strength test by using strain gages as a function of flow plate thickness, the existence of skirt and loading condition for the Korean Fuel Assembly(KOFA). The experimental apparatus was designed for load conditions, uniformly distributed load and displacement. Test method using whiffle tree of uniformly distributed load has been comparatively conservative. The test results were compared with those of finite element analysis and the test method on bottom end piece was established.

• 대한기계학회논문집A
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• 제35권4호
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• pp.417-424
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• 2011

핵연료집합체는 상단고정체, 하단고정체, 지지격자체, 제어관/계측관과 핵연료봉의 5 가지 주요 구성품으로 이루어져 있다. 여기서 상/하단고정체는 다른 구성품과 달리 ASME, Section III, Division 1 - Subsection NB 의 운전조건 A, B 에서의 stress intensity limits 를 만족하여야 한다. 이중냉각 핵연료집합체는 집합체당 출력을 증가시키기 위해서 기존의 가압경수로용 핵연료집합체에서 핵연료봉의 배열과 위치를 변화시켰는데 이로 인하여 핵연료봉 내/외부유로로 냉각수가 잘 흐를 수 있도록 상/하단고정체의 유로판의 형상을 수정하여야 한다. 본 논문에서는 설계하중조건에 대하여 수정된 상단고정체 유로판의 건전성평가를 위해 수행한 응력선형화과정을 자세히 설명하고 평가결과에 대하여 기술하였다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1999년도 춘계학술발표회요약집
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• pp.281-281
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• 1999

• 복식
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• 제55권4호
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• pp.138-150
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• 2005

Phrygia headgear has an important meaning from the perspectives of costume history and cultural exchanges in ancient times. This study is to investigate the prototype of Phrygia headgear through analysis of its manufacturing methods and styles on the basis of prior studies on ancient sculptures and literatures conducted by European researchers and to examine its history and meanings. In these ways, this study will be helpful in understanding the importance of Phrygia headgear in cultural exchanges between the East and the West. Results of this study can be summarized as follows: Phrygia headgear was orn by eastern tribes, so it was a symbol of those from the east in ancient times. Phrygia headgear is frequently found in Greek artistic works of 5th to 4th century BC that depicted eastern tribes. Also, this headgear can be observed in artistic works for Mithras, Attis, or other gods. Since Phrygia headgear's shape is similar to that of Homer's helm, many researchers believe that it might be originated from Homer's helm. This headgear made of oxen scrotum(stierbeutel) or its surrounding skin has a long end at the top. This long end is round and drooping toward the front side. From such unique shape, we top. This long end is round and drooping toward the front side. From such unique shape, we top. This long end is round and drooping toward the front side. From such unique shape, we can draw a conclusion that Phrygia headgear was made of oxen scrotum and its surrounding skin. Dependingy on drooping patterns, there are various shapes, such as the round, tightly swollen one worn by Mithras, the tongue-shaped one found in Basilika S. Apolinare Nuovo's mosaic depicting three wise men, the balloon-shaped one frequently found in Greek vases depicting Scythian, and the one drooping to the side depicted in Alexandersarkophag. Further, some Phrygia headgear has covers for neck and ears. For example, Phrygia headgear worn by Persian Satrap tribe has such covers attached to the head part. Meanwhile, Phrygia headgear worn by Amazone tribe does not show such separate covers, Rather, one piece of oxen skin was tanned and finished to make such covers. Wearing Phrygia headgear can be interpreted in several ways. Use of animal's skin for wearing things is a unique aspect in ancient societies because they believed that wearing animal skin would give them power of the animal. Further, Phrygia headgear made of oxen scrotum was a symbol of reproductive power to women.

• 한국가구학회지
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• 제15권2호
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• pp.53-62
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• 2004

This study explored the development of wood furniture made of aged Castanea crenata Sieb. et Zucc, which has been largely planted in the southern area since 1960s and has hardly been used as furniture materials. First, the physical properties of the chestnut wood including specific gravity, stiffness, and shrinkage were compared with Zelkova serrata, Acer palmatum Thunb., Fagus crenata var. multinevis, Quercus, Tagayasan, Prunus serrulata var. spontanea, Juglans sinenis, Pteronrpus santalinus, Diospyros ebenum, and Fraxinus rhynchophylla, which have largely been used in manufacturing furniture. The chestnut wood had appropliate physical properties for wood furniture like other furniture woods. A piece of small table 50 cm in width, 50 cm in length and 60 cm in height by the chestnut tree was created for a current interior space. Since the diameter of the chestnut tree planted since 1960s is below around 30 cm, the top plate of the table had to be put together by an end-joint technique using a small strip. Finally, it is expected that this study will create a greate motivation for furniture designers, furniture studios and furniture companies in Korea to use the woods from the aged chestnut tree in developing furniture in the future.

• 방사성폐기물학회지
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• 제8권4호
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• pp.347-353
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• 2010

사용후핵연료를 파이로 건식처리하면 사용후핵연료 자체 내에 존재하는 세슘, 스트론튬, 초우라늄 계열 등이 중간저장 되어 영구처분 방사선원항에서 제외되므로 사용후핵연료집합체를 구성하는 구조재, 즉 금속폐기물의 방사선원항이 중요해지게 된다. 따라서 본 연구에서는 $17{\times}17$ KOFA 사용후핵연료 10 톤이 파이로 건식처리 되었을 경우를 가정하여 각 구조재 부품별로 방사선원항 특성을 분석하였다. 우선 구조재 부품별로 질량 및 부피를 상세히 계산하였다. 핵연료 상단 및 하단 고정체에서의 중성자스펙트럼이 노심과 다르므로 각 구조재 부품별로 핵반응단면적라이브러리를 KENO-VI/ORIGEN-S 모듈로 직접 생산하였으며, 이를 적용하여 ORIGEN-S 코드로 방사화 방사선원항을 평가하였다. 평가결과 원자로 방출후 10 년 시점에서의 방사능세기, 붕괴열, 위해지수 값은 각각 $1.40{\times}10^{15}$ Bequerels, 236 Watts, $4.34{\times}10^9m^3$-water 로 나타났으며, 이는 사용후핵연료 자체 값의 0.7 %, 1.1 %, 0.1 %에 해당하는 값이다. 방사능세기, 붕괴열, 위해지수 모든 측면에서는 금속폐기물 전체물량의 1 %만을 차지하는 인코넬 718 그리드판이 가장 중요한 것으로 평가되었으며, 특히 이를 따로 분리하여 관리하면 금속폐기물 전체 방사능세기를 20~45 % 정도, 위해지수를 30~45 % 정도 감소시킬 수 있는 것으로 나타났다. 전체적으로 볼 때, 금속폐기물의 방사능세기 및 위해지수는 처분시스템 설계 시 중요한 인자로 고려되어야 하나, 붕괴열은 그 열량이 작아 중요하지 않은 것으로 나타났다.