• Journal of the Korean Home Economics Association
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• v.35 no.2
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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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• v.25 no.spc3
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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.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.24 no.2
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• pp.138-148
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• 2012

A stochastic reliability analysis model has been developed for evaluating the time-dependent stability performance of armor units of rubble-mound breakwaters subjected to the multiple loads of arbitrary magnitudes which could be occurred randomly. The initial structural capacities and the damage rates of armor units of rubble-mound breakwaters could be estimated as a function of the incident wave height with a given return period by using the modified Hudson's formula and Melby's formula. The structural stability performances of armor units of rubble-mound breakwaters could be analyzed in detail through the lifetime reliability investigations according to the limit states such as the serviceability or ultimate limit state and the conditions of multiple loads. Finally, repair intervals for the structural management of armor units of rubble-mound breakwaters could quantitatively be evaluated by a new approach suggested in this paper that has been based on the target probability for repair and the accumulated probabilities of failure obtained from the present stochastic reliability analysis model.

• Korean Journal of Materials Research
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• v.29 no.1
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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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.737-743
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• 2016

Coastal hazards such as high waves are expected to increase due to global climate change. Therefore, we investigated new armor unit structures for disaster prevention. Recently, a concrete caisson has been used in many breakwaters against high waves in South Korea, but the demand for concrete armor unit has increased due to the high cost and many installation requirements. Though many new armor units have been developed over the world since Tetrapod in 1950, few have been used due to lack of systematical development. The representative armor units in current use have many advantages, but they cannot be applied to waves higher than 8 m. One of the new armor units developed by the design guide based on recent trend and hydraulic model experiments were conducted. The new armor unit was developed as a single layer due to cost effectiveness. However, the thickness is close to 1.5 times by overlapping the alphabet A and V. It showed higher overtopping compared to a double layer because of the thickness and the high packing density. It has a high interlocking vertically but low horizontally. It shows good stability at 9 m in model testing.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.1
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• pp.15-29
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• 2009

Most breakwater armor blocks are designed by using Hudson's or van der Meer's formula. The minimum weight of armor blocks is calculated by equating the resistance to the load in each formula. The larger value is then chosen as the design weight. In this study, we have performed reliability analyses for thus designed breakwater armor blocks of 12 trade harbors and 8 coastal harbors in Korea. The probability of failure calculated by the reliability analysis provides a criterion for evaluating the stability of armor blocks. The calculated probability of failure was almost same for all the breakwaters so that we were able to quantitatively evaluate the safety level of armor blocks of existing breakwaters. We also found that the safety factor used in the deterministic design method and the probability of failure in the reliability design method show a linear relationship. Therefore the probability of failure of existing breakwaters can be quantitatively calculated from the safety factors. The calculated probability of failure could also be used for determining the target probability of failure in the future.

• Journal of Industrial Technology
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• v.24 no.A
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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.

• Journal of the Korea Fashion and Costume Design Association
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• v.9 no.1
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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.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.13 no.1
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• pp.9-17
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• 2001

A probability of failure of armor units on rubbJe-mound breakwater are evaluated by using the direct method for reliability analysis, which is represented as a function of safety factor that has been extensively used in practical design. The reliability function is fonnulated based on Hudson formula suggested for designing the stable size of armor units on rubble-mound breakwater. Several kinds of stability coefficient are applied separately to calculate the probability of failure with respect to the type of armor units, breaking/nonbreaking and the correlation coefficients between random variables. [n addition, the sensitivity analyses are carried out to investigate quantitatively into the effects of each random variable in the reliability function on the probability of failure.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.1
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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.