• Nuclear Engineering and Technology
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• 제54권8호
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• pp.2989-2998
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• 2022

Line contact structures, such as the contact between graphite brick and graphite tenon, widely exist in high-temperature gas-cooled reactors. Due to the stress concentration effect, the line contact area is one of the dangerous positions prone to failure in the nuclear reactor core. In this paper, the failure mechanism of line contact structures composed of IG11 nuclear graphite column and brick were investigated by means of experiment and finite element simulation. It was found that the failure process mainly includes three stages: firstly, the damage accumulation in nuclear graphite material led to the characteristic yielding of the line contact structure, but no macroscopic failure can be observed at this stage; secondly, the stresses near the contact area met Mohr failure criterion, and a crack initiated and propagated laterally in the contact zone, that is, local macroscopic failure occurred at this stage; finally, a second crack initiated in the contact area and developed in to a Y-shape, resulting in the final failure of the structure. This study lays a foundation for the structural design and safety assessment of high-temperature gas-cooled reactors.

• 건축역사연구
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• 제32권1호
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• pp.7-20
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• 2023

The construction method of scaffolding structures is different from Mortise and Tenon and bucket arch structure of traditional large woodwork. It forms an independent construction system-fixing nodes with knots, a large number of diagonal braces are used to fix shelves and the structures mostly contain X-shape and triangular shape details. Simple ones include stalls, sheds, rain sheds, altars, lamp racks etc. But the scaffolding with larger scale and more complicated structure are modeled on archways, theatres and other buildings which are used in commercial and festival activities. At present, Macao, Hong Kong, Guangdong, Sichuan, Shanxi and other places in China have retained the custom of using scaffolding structures in important festival activities, but their uses, techniques and building types are slightly different from place to place. Due to building and demolishing at any time, the construction and service cycle is short. As a result, there are almost no physical objects left. We can only deduce the use and technical characteristics of ancient scaffolding skills through the colorful building styles that have been preserved with folk activities in various parts of China, the craftsmanship handed down from generation to generation by the scaffolding guild and artisans, and the description of cultural and historical materials and the mutual corroboration of visual materials.

• Nuclear Engineering and Technology
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• 제27권6호
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• pp.853-858
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• 1995

노심 천 이 현상의 모사계산을 위해서는 노심상태 의 초기조건을 실제노심과 일치시켜야 하는데 특히, 제논동특성이 관심의 대상이 되는 천이현상에 있어서는 직접적인 추정이 불가능한 노심내 제논분포의 초기상태가 천이현상의 해석결과에 커다란 영향을 미치게 된다 초기상태의 노심이 정확히 제논 평형상태에 있지 않는 경우 노심의 시간에 따른 변화를 잘 예측하기 위해서는 비평형 제논분포를 모사하는 초기화가 필수적이다. 본 연구에서는 천이현상 이전에 관측된 비평형 제논진동을 등가 제논진동으로 모사하여 천이현상을 보다 정확히 예측할 수 있는 제논 초기화 기법을 개발하였으며 영광 3, 4호기 시운전 시험에서 입수된 실측자료를 통하여 그 적용성을 입증 하였다.

• 한국실내디자인학회논문집
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• 제20권3호
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• pp.190-197
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• 2011

The purpose of this study is to examine the characteristics of space design appearing in facade and interior composition factors of buildings in the colonial period in Indonesia. Research method is a field study, and subjects of the study is 14 buildings built in the colonial period located in Jakarta. The research result is as follows. First, Facade is divided into C type (colonial style), CT type (colonial style + traditional style), CA type (colonial style + art deco style), and CTA type (colonial style + traditional style + art deco style). Among them, CT type which shows both a colonial style and traditional style accounts for the most. As for Java traditional style mainly shows Joglo roof style and bratticing decoration on top of gates, and the colonial style presents both an Amsterdam canal housing style such as narrow Facade and unusual Gable, and a classical style such as pediment, entablature, and columns. Second, interior space is divided into C type (colonial style), CT type (colonial style + Indonesian traditional style), A type (art deco style), and CA type (colonial style + art deco style). Among them, CT type was also accounted for the most. Selected traditional style is a shape of bratticing decoration on top of gates and a shape of tenon of Joglo housing structure. Colonial style showed classical style such as exposed crossbeams, columns, and pilasters, and as for unique decoration, there are Ancona decoration and Delft tile decoration. On one hand, art deco style used typical art deco factors such as contrast of various materials and complementary color or golden color use as well as zigzag or vertical lines and geometric ornament by combining with colonial style or traditional style. It is expected that such research result will be a practical reference data when Korean construction companies or interior design companies advance Indonesia.

• Structural Engineering and Mechanics
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• 제40권4호
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• pp.453-469
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• 2011

A one-story, wooden-frame, intermediate-bay model with Dou-Gon designed according to the Building Standards of the Song Dynasty (A.D.960-1279), was tested on a unidirectional shaking table. The main objectives of this experimental study were to investigate the seismic performance of Chinese historic wooden structure under various base input intensities. El Centro wave (N-S), Taft wave and Lanzhou wave were selected as input excitations. 27 seismic geophones were instrumented to measure the real-time displacement, velocity and acceleration respectively. Dynamic characteristics, failure mode and hysteretic energy dissipation performance of the model are analyzed. Test results indicate that the nature period and damping ratio of the model increase with the increasing magnitude of earthquake excitation. The nature period of the model is within 0.5~0.6 s, the damping ratio is 3~4%. The maximum acceleration dynamic magnification factor is less than 1 and decreases as the input seismic power increases. The frictional slippage of Dou-Gon layers (corbel brackets) between beams and plates dissipates a certain amount of seismic energy, and so does the slippage between posts and plinths. The mortise-tenon joint of the timber frame dissipates most of the seismic energy. Therefore, it plays a significant part in shock absorption and isolation.

• 건축역사연구
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• 제21권3호
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• pp.73-92
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• 2012

This study mainly inquired characteristics and changes of 'Chang-aelgool' through 38 cases(with 161 Ssang-chang) of annex and pavillion buildings in Yeong-nam region which are built during the Chosun dynasty. The method of inquiry included actual survey of windows along with bibliographical research, and the results are as below. First, through the discovery of the term 'Chang-aelgool' as an indication of the window-forming frame in 'YeongGeonUiGwe'(1680 A.D), it is apparent that the term 'Chang-aelgool' was widely used in Korea from the late 17th century. Second, the 'Chang-aelgool' of study objects are classified into 4 categories. Type I and II are comprised of mitre-joints which cover the 4 corners of 'Chang-aelgool' and mainly used in building annex and pavillion buildings during the early period of the Chosun dynasty. Type III was widely used during the early and middle period of the Chosun dynasty and drastically dropped in number during the late period of the dynasty. Type IV is comprised of mitre-joint of the upper-half, tenon-jointing of the lower-half and widely used in annex and pavillion building during the late period of the Chosun dynasty. Third, the form of 'Chang-aelgool' has changed from rectangular form with longer width during the early period of Chosun dynasty to square form during the middle period and eventually ended up as a rectangular form with longer height during the late period of the dynasty. Fourth, it is considered that while mullion which is located in the center of 'Chang-aelgool' was mainly used around the main floored room during the early period of the Chosun dynasty, became commonly used in main floored room and 'ondol' rooms during the middle period and drastically dropped in number from then and ended up being not in use after the mid 18th century.

• 대한안과학회지
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• 제59권11호
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• pp.1056-1061
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• 2018

목적: 발프로익산이 배양된 인체 테논낭 섬유아세포의 생존에 미치는 영향에 대해 알아보고자 하였다. 대상과 방법: 일차배양한 섬유아세포에 0, 0.25, 0.5, 1.0 mM 발프로익산과 0, 1.0, $2.5{\mu}g/mL$ 미토마이신 C에 각각 또는 동시에 5일간 노출시킨 후 MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide) assay를 이용하여 세포의 생존을 측정하였고, annexin-V/propidium iodide 이중염색 후 유세포 분석을 이용하여 세포고사의 정도를 측정하였다. 결과: 발프로익산은 농도에 비례하여 섬유아세포의 생존을 유의하게 저하시켰으며, 미토마이신 C를 추가한 경우 섬유아세포의 생존을 더욱 저하시켰다. 두 약제 모두 섬유아세포의 세포고사를 유발하였으나 발프로익산은 미토마이신 C에 비해 세포고사를 적게 유발하였다. 결론: 발프로익산은 섬유아세포의 생존을 저하시키며 세포고사를 유발한다. 또한 미토마이신 C를 병용한 경우 섬유아세포에 대한 항증식효과가 더 나타날 것으로 생각된다.

• Journal of Yeungnam Medical Science
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• 제11권1호
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• pp.55-62
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• 1994

녹내장 누공수술의 대표적 수술인 섬유주절제술의 주된 실패요인인 여과포의 섬유화를 막아 수술성공율을 향상시키기 위해 항대사 물질인 Mitomycin C를 수술실패 위험이 높은 녹내장 환자 20명 25안을 대상으로 섬유주절제술중에 사용하여 섬유주절제술의 보조제로서의 Mitomycin C의 효과를 알아보았다. 전체 대상안의 수술전 평균 안압은 $38.6{\pm}6.6mmHg$였으며 수술 후 최종 평균안압은 $11.7{\pm}3.8mmHg$로 26.9mmHg의 안압감소를 나타내었다. 수술 성공율은 40세 이하의 원발광우각녹내장에서는 8안중 7안 (88%), 포도막염에 의한 속발 녹내장에서는 6안중 5안(83%), 신생혈관녹내장에서는 5안중 4안(80%)에서 성공하였고 유년녹내장과 과거 수술 기왕력이 있는 녹내장 및 무수정체녹내장에서는 6안 모두 (100%)에서 성공함으로서 전체적으로는 25안중 22안에서 성공하여 88%의 성공율을 나타내었다. 수술 후 시력 변화는 25안중 24안(96%)에서 수술전 시력에 비해 변함이 없거나 다소 호전되었으며 1안(4%)에서 시력 소실을 보였다. 술후 합병증은 전방출혈이 5안(20%), 얕은 전방이 4안(16%), 저안압증이 4안(16%), 점상각막염이 3안(12%), 결막봉합파열이 2안(8%), 낭포화된 여과포가 1안(4%), 맥락막 박리 1안(4%)에서 발생하였다. 결론적으로 섬유주절제술에서 Mitomycin C의 부가적 사용은 수술 실패 위험이 높은 녹내장에서 효과적이고 비교적 안전하게 사용할 수 있으나 장기간 경과 관찰을 통하여 안전하고 효과적인 사용법에 대한 다양한 연구가 필요할 것으로 사료된다.

• Clinics in Shoulder and Elbow
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• 제12권2호
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• pp.207-214
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• 2009

목적: 관절경 하 회전근 개 봉합에서 일반적으로 건-봉합간 접촉면 (tenon-suture interface) 에 약한부위 (weak link)가 형성되어 있어 관절경 하 회전근 개 봉합은 개방적 봉합술보다 높은 재파열율을 가진다. 이 연구의 목적은 봉합사를 뼈에 고정할 때 관절경으로 사용할 수 있는 UU (Ulsan University) 봉합과 개방적 변형 MA (Mason-Allen) 봉합의 강도를 비교하는 것이다. 대상 및 방법: 한 구의 사체 극상근 건을 채취하여 절반으로 나눈 후 다시 절반을 나누어 사체의 어깨 관절 한 구당 네 개의 건을 만들어 총 24개의 검체를 만들었다. 두 봉합 형태 (UU, MA)는 무작위로 선택하였으며 각각의 건에 시행하였다. 검체는 0.25 Hz에서 5~30N의 조절된 외력하에서 50회 주기 부하 (cyclic loading)를 받았다. 각 검체는 초당 1mm의 전이가 되는 상황하에서 파열이 발생할 때(ultimate tensile load)까지 부하를 받았다. 조건 이완 (condition elongation), peak-to-peak 전이(displacement), 기울기 (stiffness), 최대 인장력 (ultimate tensile load), 파열 양상 (mode of failure) 등을 기록하였다. 결과: 주기 부하 실험에서 두 봉합 형태 간 유의 있는 차이는 없었다. 최대 장력 실험에서 UU 봉합과 변형 MA (Mason-Allen) 봉합 간에 통계학적으로 유의한 차이는 없었다 (109.4 N, and 110.6 N). 양 봉합 형태에서 가장 흔한 파열 양상은 봉합의 빠짐 (suture pull-out)이었다. 결론: UU 봉합과 변형 MA 봉합은 유사한 생역학적 특성을 가진다.