• Proceedings of the KWS Conference
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• 2001.05a
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• pp.224-227
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• 2001

In this study, CT specimens were prepared hem ASTM SA516 which was used for pressure vessel plates for room and low temperature service. And we got the following characteristics from fatigue crack growth test carried out in the environment of room and low temperature at $25^{\circ}C$, -3$0^{\circ}C$, -6$0^{\circ}C$, -8$0^{\circ}C$, -l$0^{\circ}C$ and -l2$0^{\circ}C$ and in the range of stress ratio of 0.1, 0.3 by means of opening mode displacement. At the constant stress ratio, the threshold stress intensity factor range $\Delta K_{th}$ in the early stage of fatigue crack growth ( Region I ) and stress intensity factor range $\Delta$K in the stable of fatigue crack growth ( Region II) was increased in proportion to descend temperature. It assumed that the fatigue resistance characteristics and fracture strength at low temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region. The straight line slope relation of logarithm da/dN - $\Delta$K in Region II, that is, the fatigue crack growth exponent m increased with descending temperature at the constant stress ratio. It assumed that the fatigue crack growth rate da/dN is rapid in proportion to descend temperature in Region H and the cryogenic-brittleness greatly affect a material with decreasing temperature.

• Journal of Applied Biological Chemistry
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• v.61 no.3
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• pp.283-290
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• 2018

In this study, we verified the 1-1-diphenyl-2-picryl-hydrazyl radical scavenge, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenge, elastase, tyrosinase inhibitory effect by using the solvent fractions of Maekmoondong-tang hot water extract. As a result, the ethyl acetate fraction (MW-EA) showed the highest inhibitory activity. In cell-based assays, MW-EA treatment confirmed a 34% ($100{\mu}g/mL$) efficacy in reactive oxygen species inhibitory activity, and at the same concentration, MMPs showed more than 50% inhibition and tyrosinase inhibited 25% ($50{\mu}g/mL$). Therefore Maekmoondong-tang is considered high development potential as a material to improve the skin.

• Journal of Korea Foundry Society
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• v.32 no.6
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• pp.276-283
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• 2012

This study presents the results on the changes of crucible thermal conductivity and inflow of Ar, and constructed the mathematical model about heat transfer into furnace. As process variables, simulation model was designated thermal conductivity of crucible to $0.5W{\cdot}m^{-1}{\cdot}K^{-1}$, $1W{\cdot}m^{-1}{\cdot}K^{-1}$, $2W{\cdot}m^{-1}{\cdot}K^{-1}$, $4W{\cdot}m^{-1}{\cdot}K^{-1}$, and inflow rate of Ar to 15 L/min, 30 L/min, 60 L/min. Initial condition and boundary condition were set respectively in two terms of process. Each initial conditions were set up by the preceding simulation of heat and fluid flow. The primary goal is the application of unidirectional growth of Si ingot using the result. In the result of the change of heat conductivity of crucible, the higher thermal conductivity of crucible shows the shorter solidification time and the bigger temperature difference. And the flow patterns are changed with the inflow rate of Ar. Finally, we found that the lower crucible's thermal conductivity, the better crucible is at polycrystalline Si ingot growth. But in case of Ar inflow, it is hard to say about good condition. This data will be evaluated as useful reference used in allied study or process variable control of production facilities.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.1
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• pp.45-49
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• 2008

The development of manufacturing process of silicon (Si) ingots is one of the important issues to the growth of the photovoltaic industry. Polycrystalline Si wafers shares more than 60% of the photovoltaic market due to its cost advantage compared to mono crystalline silicon wafers. Several solidification processes have been developed by industry including casting, heat exchange method (HEM) and electromagnetic casting. In this paper, the advanced directional solidification (ADS) method is used to growth of large sized polycrystalline Si ingot. This method has the advantages of the small heat loss, short cycle time and efficient directional solidification. The numerical simulation of the process is applied using a fluid dynamics model to simulate the temperature distribution. The results of simulations are confirmed efficient directional solidification to the growth of large sized polycrystalline Si ingot above 240 kg.

• The Research Journal of the Costume Culture
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• v.20 no.2
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• pp.222-237
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• 2012

Air-containing fashion, which can offer diverse functions through the inflow and outflow of air, is highly relevant in today's mobile society, where people are experiencing a wider range of environments. This study attempts to suggest the possibility of air-containing multi-functional fashion that could continuously be utilized by developing a design for an air-containing jacket using modular systems. In this research, the modular systems in architecture and furniture design were referenced through a review of the literature for the purpose of establishing modular systems in fashion. Functions relevant to the mobility of today's society are derived from the results of advanced research and applied to the design of modules of the jacket. The modules are integrated through the modular systems. The folding and unfolding structure in architecture and furniture is applied as a folding system in fashion, the vertical accumulation structure as a layering system, and the horizontal integration structure as a combining system, and in addition, the containing system has emerged in fashion. Each module is designed to fulfill certain functions, such as cushioning, heat insulation, and portability. The folding system is utilized in designing the cushion module to support the neck and back of a wearer by making its hood and hem fold in the back. The application of a layering system was suggested by making the vest, combined with the neck cushion and back cushion via the combining system, layered with its insulation module. By applying the combining system, the hood that includes the neck cushion, the skirt that includes the back cushion, the body that includes the insulation module, and the sleeves can be connected and separated by a zipper. The applicability of this concept was proven by applying a developed design to an actual item.

• The Research Journal of the Costume Culture
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• v.21 no.2
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• pp.261-271
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• 2013

This study aimed to identify professional climbers'demand for movement functionality in pants worn for rock climbing and ice climbing. Data were collected through in-depth interviews with 12 professional climbers using a semi-constructed questionnaire. The respondents were instructor-level experts whose climbing ability ranged from 5.9 to 5.14 on the Yosemite Decimal System rating scale. The research findings were as follows. Experts wore different climbing pants depending on the type of climbing. For example, they mostly wore high-stretch, second layer pants for rock climbing, while layering first layer, second layer, and third layer pants for ice climbing. There were gender differences regarding the parts of the body in which climbers reported the most discomfort when wearing climbing pants; male climbers most commonly responded 'knees', 'inner thighs' and 'hips' while their female counterparts most commonly responded 'inner thighs', 'exposed back and waist' and 'hips' in that order. Differences were found between rock climbing and ice climbing in terms of wear and tear on pants, preferred fabric properties, and length of pants. Wear and tear was found mainly on the hips and knees of rock climbing pants and on the inner lower hem of ice climbing pants. Listed in the order of preference, the most preferred fabric properties were elasticity, light weight, and durability for rock climbing pants and elasticity, insulation, and protection against water and wind for ice climbing pants. Regarding the length of rock climbing pants, respondents preferred ankle-length pants and cropped pants that did not cover the feet. For ice climbing pants, respondents favored heel-length pants that prevented pieces of ice from entering the clothing. Men showed a high level of preference for ergonomically cut climbing pants. Respondents said the waistband on climbing pants should be simplified so as not to adversely affect climbing maneuvers.

• The Research Journal of the Costume Culture
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• v.21 no.2
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• pp.246-260
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• 2013

This research was carried out on women in their 20s and 30s who have overweight lower body. The subjects selected for this study were women a Rohrer index of 1.6 or higher, a waist circumference 78.5cm to 83.5cm, and a lower drop of at least 18cm. The aim is to propose a prototype of bi-stretch pants meeting demands for both functionality and aesthetic appeal. Various clothing patterns ease amount of the waist and hip circumferences and crotch depths and were developed. They had different crotch widths, and center back line angles. The results showed that the best pants patterns were ease 1cm to the total hip circumference. The front hip circumference was H/4-0.5cm, and the back hip circumference was H/4+1cm. The front crotch width was H/20+1cm, the back crotch width was H/10+3cm. No additional ease was given to the total waistline. The front waist circumference was W/4+0.5cm. The back waist circumference was W/4-0.5cm. The knee circumference was set at 44cm, the pant hem width was set at 36cm, and the pant length was set at 100cm-5cm. The findings of this research can be used as basic data for stretch pants that fit the abdomen, hips, and thighs for women in their 20s and 30s with overweight lower body.

• Journal of the Korea Fashion and Costume Design Association
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• v.14 no.4
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• pp.113-125
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• 2012

This study, as one on the neck design of seamless knitwears, set out to make experimental clothes applying various knitting methods to the hem of round neck, seek the knitting methods of finishing touches on the ending part of round neck to enhance function and aesthetic appreciation through measuring tensile strength and assessing wearing sensation, and provide basic data that would be of practical help to developing the design of seamless knitwears and mass production in the national knit industry. The ending part of neck of the seamless knitwear is not only the last stage in making knitwear but also affects the function and appearance of the clothes. The investigator, thus made six different pieces of experimental clothes according to the finishing methods of knitting on the neck, then measured tensile strength and put them to the test by a group of experts for the assessment of wearing sensation. The results were analyzed based on variance analysis(ANOVA), and the items with similar results were put to the Duncan test for intergroup comparison. According to the analysis results of measuring tensile strength, Experimental Clothes B received the highest evaluation, Experimental Clothes E the lowest. Also Experimental Clothes B was ranked the highest in almost every evaluation criteria, whereas Experimental Clothes E was ranked the lowest in the assessment of wearing sensation.

• Journal of the Korean Home Economics Association
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• v.34 no.2
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• pp.43-55
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• 1996

The purpose of this study was to investigate the slacks pattern making on the movement-fitness of the knee region. The experimental items were divided into the lower limb movement (M1~M5) and slacks pattern designs (4 : basic pattern, in-pleats, side-pleats, seam-line increase). This study was done by clothing pressure test, sensory evaluation test and the difference shape-transformation of wearing-slacks. The summarized finding resulted from experiments and investigation are suggested as follows ; First, the clothing pressure test showed that the order of clothing pressure in the movement was the rabbit leap movement (M3), the sit on knees (M4), the nobleman sitting (M5), the sit on chair (M2) from the highest to the lowest. In the comparison of clothing pressure tested by blocks of lower-limb, center front knee region shows the highest of 300g/cm2. In it by constructional methods, the clothing pressure of in-pleats, side-pleats methods shows lower than basic pattern, hem-line increase methods. Also in comparison of the two methods, in-pleats method shows lower than side-pleats method. Second, by the sensory evaluation test based on the lower-limb movements and constructional methods of slacks, it was found that the functional factor score of the rabbit leap movement was also the waist, hip, knee region was the lowest in all blocks. And in the comparison of constructional methods, in-pleats method was the highest in all methods. Third, in consideration of the difference in the shape-transformation of wearing-slacks on the movement-fitness, pleats pattern design methods showed that the ratio of shape-transformation was lower than basic on seam-line increase methods. But the difference of the side-pleats and in-pleats methods was litle. According to these investigation, the slacks pattern making caused by movement-fitness on the knee region, in-pleats design method was the functional slacks pattern.

• Journal of the Korean Society of Costume
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• v.55 no.1 s.91
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• pp.113-128
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• 2005

To find our own individuality, there must be an active study on jeogori which is an unexplored field. Therefore, the purpose of this study is to consider artistic beauty and predominance of jeogori and recognize it as a precious culture, and also encourage interest about traditions. The range of this study is ancient times to Chosun dynasty, and in this study which will be the first part, the range is till the era of the Three Kingdoms. The study about jeogori is based on mural paintings of Goguryeo burial mounds, clay dolls and remains during Shilla, Beakjae, and United-shilla era. The contents of this study is 1. research the origin of jeogori's detail structures and changes of the form, 2. analyze the form and structure of the jeogori in each era, and therefore 3. find the predominance of Goguryeo costume by considering functional and design aspects. Therefore the conclusion of this study about the era of the Three Kingdoms are First, jeogori of the three kingdom era were developed from ancient times caftan style which Korea, China and Japan wore all together. Second, the structure of the jeogori during the Three Kingdom are ryeongeum, gil, somae and seon. Third, there is a special line that starts from the neckline and ends at the hem line which should be called ryeongeum in my opinion. Forth, while researching Goguryeo murals there were both left and right sided open jeogori. therefore, I would like to set up a new theory that during the ancient times to Three Kingdom era, not did China's clothing effected the Korean costume but the costume in east asia shared their forms all together.