• 대한가정학회지
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• 제35권2호
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• pp.111-122
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• 1997

This thesis researched for the conservation of a suit of armor, one glove, one belt, and on knife case that General Jung, Gong-chung had been worn in the early 17 th centuries. The armor was Doojung-kab for the battle. It was made of two kinds of fabrics, one of them was silk satin's outer fabrics, the other was quilt4d cotton's lining. as the armor was made of silk and cotton, it was treated by dry solvents and dry soap. In the dry cleaning method, used solvents were n-hexane, cyclohexane, benzene, and n-decane. the volume ratio of dry soap was 120: 1. The reaction temperature was 30℃, and reaction time was 10 to 30 minutes per one turn. The glove, belt and knife case were made with leather. They were dipped on the polyethyleneglycol 150 saturated solution during 24hours at 50℃ and then dried naturally. They were washed by toluene to remove the untreated pp.E.G. on the surfaces. It was sterilized by two gases of methylenebromide and ethyleneoxied. For the conservation, it was packed thoroughly by ？ polyethylene film sheet without air.

• Ocean and Polar Research
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• 제25권spc3호
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• pp.417-421
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• 2003

In the reliability design of the breakwater armor layer, it is often necessary to calculate its damage accumulated over the life of the breakwater. In this paper comparison is made between the two methods proposed by Hanzawa et at. in 1996 and Melby and Kobayashi in 1998 to calculate the cumulative damage of the breakwater armor layer. Tn the case where a severe damage occurs at the beginning of the life or toe breakwater, the two methods do not show significant difference, but in general the farmer predicts a cumulative damage several times larger than the latter.

• 한국해안·해양공학회논문집
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• 제24권2호
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• pp.138-148
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• 2012

경사제에 불규칙하게 작용하는 임의 크기의 다중하중으로 인해 피복재의 안정성에 대한 성능이 시간에 따라 어떻게 달라지는지를 해석할 수 있는 추계학적 신뢰성 해석 모형이 개발되었다. Hudson의 공식과 Melby 공식을 이용하여 재현기간에 따른 파고의 함수로 경사제 피복재의 초기 저항력 크기와 피해율을 확률적으로 산정할 수 있는 새로운 방법이 제시되었다. 생애기간에 대한 신뢰성 분석을 실시하여 시간에 따른 다중하중의 작용과 사용한계나 극한한계 등 한계상태에 따른 구조물의 성능을 올바로 해석할 수 있었다. 마지막으로 보수보강 목표확률을 시간에 따른 누적파괴확률의 결과와 조합하여 구조물 유지관리에서 가장 중요한 변수인 보수보강 시점을 정량적으로 산정할 수 있는 방법이 제시되었다.

• 한국재료학회지
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• 제29권1호
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• pp.43-51
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• 2019

Nacre of abalone shell features a "brick-and-mortar" microstructure, in which micro-plates of calcium carbonate are bonded by nanometers-thick layers of chitin and proteins. Due to the microstructure and its unique toughening mechanisms, nacre possesses an excellent combination of specific strength, stiffness and toughness. This study deals with the possibility of using nacre fragments obtained from abalone shell for making a bulletproof armor system. A composite plate laminated with abalone shell fragments is made and compression and bend tests are carried out. In addition, a bulletproof test is performed with hybrid armor systems which are composed of an alumina plate, a composite plate, and aramid woven fabric to verify the ballistic performance of nacre. The compressive strength of the composite plate is around 258.3 MPa. The bend strength and modulus of the composite plate decrease according to the plate thickness and are about 149.2 MPa and 50.3 GPa, respectively, for a 4.85 mm thick plate. The hybrid armor system with a planar density of $45.2kg/m^2$, which is composed of an 8 mm thick alumina plate, a 2.4 mm thick composite plate, and 18 layers of aramid woven fabric, satisfy the NIJ Standard 0101.06 : 2008 Armor Type IV. These results show that a composite plate laminated with abalone shell fragments can be used for a bulletproof armor system as an interlayer between ceramic and fabric to decrease the armor system's weight.

• 한국산학기술학회논문지
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• 제17권6호
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• pp.737-743
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• 2016

기후변화로 인해 파랑에 의한 해안의 피해는 전세계적으로 점차 증가하고 있으며, 이에 대응하기 위한 새로운 방재구조물의 연구도 활발히 진행되고 있다. 최근에는 고파랑에 대응하기 위해 한국에서는 방파제에 콘크리트 케이슨을 사용하는 경우가 많아지고 있으나, 고비용과 많은 요구조건으로 인해 소파블록의 필요성도 증가하고 있다. 1950년 Tetrapod 개발 이후 해외뿐만 아니라 국내에서도 많은 형태의 소파블록들이 개발되었으나, 체계적으로 개발되지 못해 소수의 소파블록만이 사용되고 있다. 그러나 기존의 소파블록은 많은 장점에도 불구하고, 8 m 이상의 고파랑에 적용하기 어려운 문제점을 가지고 있다. 새로운 소파블록은 최근의 개발방향에 맞추어진 설계지침에 따라 개발되었으며, 많은 형상의 후보들이 만들어졌다. 본 논문에서는 이중 한 개 형상을 선택하여 수리모형실험을 실시하였다. 신형 소파블록은 경제성을 고려하여 1층적으로 개발되었으나, 영문자 A와 V가 겹쳐진 구조로 적층 두께는 1.5층적에 가깝다. 신형소파블록은 이런 적층 두께와 높은 설치 밀도로 인해 2층적 소파블록에 비해 조금 높은 월파량을 보여주었다. 신형소파블록은 위아래는 높은 인터락킹을 가지고 있으나, 좌우로는 약한 지지력을 가지고 있다. 수리모형실험 결과 파고 9 m에서도 안정성이 검증되었다.

• 한국해안·해양공학회논문집
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• 제21권1호
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• pp.15-29
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• 2009

방파제 피복 블록은 주로 Hudson 공식과 van der Meer 공식을 사용하여 설계되고 있다. 각 공식을 사용하여 저항과 하중이 같아지는 최소 중량을 각각 산정하며 그 중 큰 값을 설계중량으로 채택한다. 이렇게 설계된 국내 무역항 12곳과 연안항 8곳의 방파제 피복 블록에 대하여 신뢰성 해석을 수행하였다. 신뢰성 해석 결과 산정된 파괴확률은 각 항만별 피복 블록의 안정성을 평가하는 기준이 된다. 최소 중량으로 설계한 경우에 파괴확률은 모든 항만에서 거의 비슷하게 계산되어 기존 방파제 피복 블록의 안전수준을 정량적으로 평가할 수 있게 되었다. 그리고 결정론적 설계법의 설계 기준인 안전율과 신뢰성 설계법의 설계 기준인 파괴확률은 뚜렷한 선형관계를 이루고 있다는 것을 확인했다. 이를 통해 기존 구조물의 파괴확률은 안전율을 통해 정량적으로 파악할 수 있게 되었다. 이 결과는 향후 방파제 피복블록의 목표파괴확률을 결정하는 중요한 자료로 사용될 것이다.

• 산업기술연구
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• 제24권A호
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• pp.215-226
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• 2004

A dynamic reliability model which can take into account the time history of loading sequences may be applied to the analyses of the hydraulic stability of armor units on rubble-mound breakwaters. All the parameters related to the stability of structures have been considered to be constants in the deterministic model until now. Thus, it is impossible to study the effects of some uncertainties of the related random variables on the stability of structures. In this paper, the dynamic reliability model can be developed by POT(Peak Over Threshold) method in order to take into account the time history of loading sequences and to investigate the temporal behaviors of stability of structure with its loading history. Finally, it is confirmed that the results of dynamic reliability model agree with straight- forwardly those of AFDA(Approximate Full Distribution Approach) of the static reliability model for the same input conditions. In addition, the temporal behaviors of probability of failure can be studied by the dynamic reliability model developed to analyze the hydraulic stability of armor units on rubble-mound breakwaters. Therefore, the present results may be useful for the management of repair and maintenance over the whole life cycle of structure.

• 한국의상디자인학회지
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• 제9권1호
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• pp.71-87
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• 2007

Main role to expand the fashion in the middle age was played by aristocracy and knight. They contributed to the fashion of the middle age regardless of aesthetic sense. First, in any age, there was a self-display design using splendid decoration or material in the costume of high-class people. Aristocracy, especially, knight in the middle age classified themselves from others by wearing the costume suitable for their statuses. Second, the Crusade knight appearing all over the cinema gathered various peoples and caused acute optic angle about specialty of costume. Therefore the trend preferring foreign costumes was changed to new fashion while it was connected to desire searching for a change. Third, although armor of knight was created because of protection in the war, in the 13th century, its character of motion and defense was emphasized and it became splendid style. More over, the costume of knight was developed to more emphasize masculine beauty with heavy upper body and light lower body so it caused sexual difference of costume in the middle age. Fourth, As knight searched effective defensive weapon, chain mail was relegated by plate armor. The order of armor that the hight wore in 1350 was as follows. First, he wears adhesive shirts, braies, hose and wears metal protector on arm and leg. He wears padded undercoat called gambeson, hauberk, plate armor and surcoat on them.

• 한국해안해양공학회지
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• 제13권1호
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• pp.9-17
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• 2001

신뢰성 해석을 위한 직접계산법을 이용하여 경사제 피복재의 파괴확률이 안전계수의 함수로 산정되었다. 신뢰함수를 수립하기 위하여 현재 설계에서 가장 많이 적용되고 있는 Hudson 공식을 사용하였다. 제체의 경사, 피복재의 종류, 쇄파 및 비쇄파 그리고 각 확률변수의 상관성에 따른 안전계수와 파괴확률의 관계가 제시되었다. 또한 신뢰함수에 포함된 각 확률변수의 변동계수에 따른 영향이 민감도 분석을 통하여 정량적으로 해석되었다.

• 설비공학논문집
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• 제11권1호
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• pp.18-30
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• 1999

A heat transfer analysis for the two-dimensional (2-D) steady state using finite difference method (FDM) is performed to predict the thermal behavior of the primary first-wall (FW) system of fusion reactor under various geometric and thermo-hydraulic conditions, such as the beryllium (Be) armor thickness, pitch of cooling tube, and coolant velocity. The FW consists of authentic steel (type 316 stainless steel solution annealed) for cooling tubes, Cu for cooling tubes embedding material, and Be for a protective armor, based on the International Thermonuclear Experiment Reactor (ITER) report. The present 2-D analysis, the control volume discretized with hybrid grid (rectangular grid and polar grid) and Gauss-Seidel iteration method are adapted to solve the governing equations. In the present study, geometric and thermo-hydraulic parameters are optimized with consideration of several limitations. Consequently, it is suggested that the adequate pitch of cooling tube is 22-32mm, the beryllium armor thickness is 10-12mm, and that the coolant velocity is 4.5m/s-6m/s for $100^{\circ}C$ of inlet coolant temperature. The cooling tube should locate near beryllium armor. But, it would be better for locating the center of Cu wall, considering problems of material and manufacturing. Also, 2-D analysis neglecting the axial temperature distribution of cooling tube is appropriate, regarding the discretization error in axial direction.