• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.431-436
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• 2002

The purpose of this study is to evaluate resistance capacity of the damaged wall structural system against earthquake ground accelerations. Two lumped damage models(5 story, 12 story) are investigated by nonlinear time history analysis. As a result of analyses, the effect of stiffness degradation due to structural damages might change the interstorydrift of the structure. Therefore the increasing interstorydrift of damaged structures might be applied to evaluate the seismic performance of damaged structures.

• 한국건설관리학회논문집
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• 제24권4호
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• pp.14-24
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• 2023

본 연구의 목적은 커튼월의 내진성능을 향상시킨 커튼월 제품을 개발하고, 층간변위시험을 실시하여 내진성능을 검증하는 것이다. 이를 위하여 (재)한국건설생활환경시험연구원의 옥외실증센터에서 커튼월 시험체를 2개층 이상으로 제작하고 지진하중과 유사한 변위량을 유발한 후 커튼월의 파손상태를 확인하였다. 1차 시험을 실시한 결과, 내진등급(특) 기준에서는 커튼월 시제품의 프레임과 유리 파손이 발생되지 않았으나, 내진등급(I)과 내진등급(II ) 기준에서는 Weather Sealant가 일부 파손되었다. 그리고 AAMA 501.6(동적내진시험)에서 정한 최대 층간변위량 150mm를 가압하였을 때 유리가 파손되는 현상이 발생되었다. 2차 시험을 실시한 결과, 내진등급(특), 내진등급(I), 내진등급(II), AAMA 501.6에서 유리가 파손되는 문제가 발생되지 않았다. 따라서, 본 커튼월 시제품의 내진성능 시험을 실시한 (재)한국건설생활환경시험연구원에서 2016년 9월 경주 5.8 규모와 2017년 11월 포항 5.4 규모의 지진에도 커튼월 프레임과 프레임 간의 탈락, Weather Sealant의 찢어짐 그리고 유리가 파손되는 피해가 없을 것으로 사료된다는 판단을 받았다.

• Computers and Concrete
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• 제7권6호
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• pp.523-532
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• 2010

If an infill wall in a reinforced concrete frame is shorter than the column height and there is no initial gap between the column and the infill wall, the short column effect can occur during an earthquake shaking. This form of damage is frequently observed in many earthquake-damaged buildings all around the world and especially in Turkey. In this study, an effective method, which consists of placing additional infill wall segments surrounding the short column, to prevent this type of failure is examined. The influence of adding infill wall in the reduction of the shear force in the short column is also investigated. A parametric study is carried out for one-storey infilled frames with one to five bays using the percentage of the additional infill wall surrounding the short column and the number of spans as the parameters. Then the investigation is extended to a case of a multistorey building damaged due to short column effect during the 1998 Adana-Ceyhan earthquake in Turkey. The results show that the addition of the infill walls around the potential short columns is an effective way to significantly reduce the shear force.

• 한국안전학회지
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• 제30권6호
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• pp.40-47
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• 2015

In this study, temperature characteristics and fire damage form were analyzed to investigate flame spreading form and fire probability from ignition sources subject to drivit component materials which is finishing material in architecture. Ignition sources were limited to a gas torch and exterior panel board fire, and the size of the sample was manufacture in 30 cm length ${\times}$ 50 cm height ${\times}$ 5cm thickness size. Marble (inner wall) + 3 mm drivit (outer wall), marble (inner wall) + 4 mm plaster stone (outer wall), sandwich panel + 3 mm driver bit (outer wall), sandwich panel + 3 mm driver bit + insulation (outer wall), and gypsum board (inner wall) + 3 mm drivit (outer wall) were prepared for the sample. As result of the research for temperature characteristics, large temperature difference by each material was shown in $218^{\circ}C{\sim}995^{\circ}C$ at 30 seconds and $501^{\circ}C{\sim}1078^{\circ}C$ at 300 seconds. Especially when the inner wall was a plaster board, lowest temperature of $501^{\circ}C$ was shown at 300 seconds and marble inner wall showed the following lowest temperature of $900^{\circ}C$. Temperature rising over $1000^{\circ}C$ was shown in other materials. Regarding fire damage form, drivit or gypsum board outer wall parts exposed to fire showed combustion and carbonization to show calcination(breaking phenomenon) and influence of heat exposure was higher as calcination became more severe.

• 설비공학논문집
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• 제19권11호
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• pp.782-788
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• 2007

In this paper, the freezing process of the water supply pipe in the exterior wall of an apartment house was analyzed by numerical method. The thickness of the pipe insulation and the percentage of insulation damage were considered as parameters in this paper. In the cases of the 0%, 8% and 20% damaged of the 5mm thickness insulation, the freezing was completed after 13 hours, 10 hours and 7 hours respectively. And in cases of the 10mm thickness insulation, the freezing was completed after 18 hours, 10.5 hours and 8 hours respectively. As a result, it is predicted that the water freezing would occurred when the water supply pipe with 8% or 20% damaged insulation are installed in the exterior wall. However, the water freezing would not occurred when the water supply pipe with 10mm thickness insulation of 0% damage is installed in the exterior wall.

• 한국지진공학회논문집
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• 제13권5호
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• pp.41-50
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• 2009

지진피해를 입은 건물의 주된 관심사는 건물에 남아 있는 내진성능 및 여진에 대한 안전성을 판단하는데 있다. 따라서 지진피해를 입은 지역 사회의 조속한 복귀를 위해서는 건물의 잔존내진성능 평가방법을 확립해 두는 것이 필수적이다. 본 연구에서는 무보강 조적채움벽체를 갖는 RC 건물의 잔존내진성능 평가방법 개발을 주목적으로, 전형적인 학교건물을 대상으로 축력레벨을 변수로 한 실스케일, 단층 1스팬 실험체를 제작하여 정적 반복가력실험을 실시하였다. 실험 중 잔존내진성능을 판정하는데 유용한 정보 중 하나인 잔류균열폭을 상세히 측정하였다. 본 논문에서는 잔류균열폭과 잔존내진성능과의 관계에 대해서 실험적, 해석적으로 검토하고 잔존내 진성능 평가를 위한 각 손상도 레벨에 대응하는 내진성능 저감계수를 제안한다.

• 한국지반신소재학회논문집
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• 제19권4호
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• pp.95-109
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• 2020

본 연구에서는 휴대형 동적콘관입시험(DCPT)을 활용하여 손상된 보강토옹벽의 피해원인을 규명하고 대책방안을 마련한 총 6곳의 현장사례를 검토하여 휴대형 동적콘관입시험의 현장 적용성을 평가하였다. 현장에서는 하부 로트의 결합 연장을 통하여 6m 이상의 지반조사가 가능하도록 개량된 동적콘관입시험기를 사용하였으며, 그 결과를 표준관입시험 결과와 비교하여 상관 관계를 분석하였다. 다양한 현장 적용사례 분석을 통하여, 휴대형 동적콘관입시험이 손상된 보강토옹벽 현장에서의 적용이 매우 편리하며, 연속적으로 개략적인 지반강성을 파악하여 옹벽의 피해원인을 규명하고 안정성을 확인하는데 큰 역할을 할 수 있음을 알 수 있었다. 또한, 동적콘관입시험 및 표준관입시험 결과를 비교, 분석해 본 결과, 사질토 지반에서는 N≒(1/3~2/3)·Nd 정도의 상관관계가 나타남을 알 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제6권4호
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• pp.270-277
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• 1996

A bacteriocin-producing strain, DU-0608, was isolated from Kimchi and identified as Leuconostoc mesenteroides subsp. mesenteroides. The bacteriocin from isolate was inhibitory against Listeria monocytogenes, Micrococcus luteus and several strains of lactic acid bacteria. The bacteriocin was inactivated by pepsin, trypsin, $\alpha$-chymotrypsin, protease, $\alpha$-amylase and lipase, but not by catalase or by heating at $100^{\circ}C$ for 60 min. The molecular weight of the bacteriocin was estimated approximately 6 kDa. The inhibitory effect was bactericidal and rapid. Following treatment with isolate bacteriocin, cells of indicator strain (Lactobacillus sake JCM 1157) were damaged at the end regions of the cell wall, whereas the cells treated with nisin were damaged at many places around the cell wall.

• Applied Microscopy
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• 제13권1호
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• pp.31-40
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• 1983

Ultrathin sections of intact mycelia, released protoplast and fused protoplast of Micromonospora rosaria were observed by electron microscopy Intact mycelia showed a typical gram-positive bacterial cell wall structure and mesosomes. Released protoplasts had no cell wall components and fibrous nuclear region was distinguished from cytoplsmic region clearly. Protoplasts which treated with sucrose supplemented buffer were stable. But those treated with buffer without sucrose were extensively damaged, forming mom braneous vesicles. It was surmised that those vesicles originated from the damaged cytoplasmic membrane. High frequency of fusion was achieved by 50%(w/v). polyethylene-glycol 1,000 Fusion bodies in different stage of fusion were observed. Cell membrane barrier was stepwise relieved.

• 한국식품저장유통학회지
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• 제7권1호
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• pp.124-131
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• 2000

Antibacterial activities of powdered spices(garlic , ginger, cinnamon and clove) against pathogenic Escherichia coli )157:H7 and Staphyloccus auresus were investigated. Spice powder was added in was exponetial phase of each bacterial culture . Growth inhibition was determined by the absorbance at 660nm and morphological changes of the cells were observed by transmission electron microscope (TEM). Ginger powder has the highest antibacterial activity, following cinnamon , clove and garlic has the least activity.Growth of Escherichia coli O157:H7 and Staphyloccus aureus were completely inhibited within 5 hours after addition of 1 % of garlic , 0.3% of ginger or cinnamon , 0.5% of clove powder on the exponential phase of the cells. Spice untreated cells of E. coli and S. aureus, the cytoplasm was entirely surrounded by rigid cell wall and cell walls formed a smooth layer well attached to the plasma membrane. In the cells of E. coli and S. aureus treated with spice powder, cell wall and plasma membrane were lysed and severely damaged. E.coli cells growth in the presence of spice powder showed plammolysis, the loss of electron dense material, the formation of extra cellular blebs and cytoplasm burst out from the cell. S .sureus cells grown in the presence of spice powder showed swell of cell wall, the loss of electron dense material , coagulation of cell cytoplasm and formation of extra cellular blebs. Severely damaged cells of S. aureus lost whole cytoplasm and left as ghost of the cell. Spice powder stimulated autolyssi and induced cell death.