• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 제7회 압연 심포지엄
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• pp.73-76
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• 2009

Increase in tensile strength of steel is important for fuel efficiency and $CO_2$ reduction. But the higher the strip strength, the more defect could be generated in hot strip mill. This study focuses on line-type edge scab. One of the causes for the defect is initial edge cracks commonly observed on a slab but their correlation has not been verified yet. Thus, the objective of this report is to verify if the edge crack is exactly the seed for edge scab. For this, we conducted pilot hot rolling test with cracked slab and compared the development of cracks and edge scabs on hot-rolled strip.

• 소성∙가공
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• 제8권2호
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• pp.200-207
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• 1999

To increase dimensional accuracy of strip width, model to compensate width spread during roughing mill has been developed. To measure the amount of width spread during the production rolling more precisely, special roughing rolling procedures for the horizontal rolling and dog-bone rolling were designed in the actual production mill. From the operational data analysis, it is known that the prime factors influencing on the width spread were strip width, strip thickness, edging amount, number of pass and type of edger roll etc., Based upon the statistical analysis of rolling data, new models which can predict width spread during horizontal rolling and dog-bone rolling were developed and tested on the actual processing conditions for the reliability. The application test showed that newly developed model gave fairly accurate predictions on the width spread during roughing passes.

• 소성∙가공
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• 제12권7호
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• pp.668-674
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• 2003

Rigid-plastic finite element analyses on the deformation of slabs at various width reductions have been performed. By using commercial finite element code, dog-bone profile, crop profile and the longitudinal width profile after edging and Horizontal rolling have been analysed. The deformation behavior of slab for the heavy edger mill has also been compared with that for the sizing press. From the deformation analyses, it was found that the sizing press-horizontal rolling method is more efficient in width reduction than that of heavy edger mill-horizontal rolling. The results of finite element analyses fer the deformation of slab were well confirmed by the actual operational data. It was found that the amount of width variation after sizing and rolling is about 5∼10mm.

• 복식
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• 제17권
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• pp.83-91
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• 1991

I observed the meaning and the symbolic charaeters about the color and style of clothes appearing at "GER GA JAP BOK GO" written by Kyu Soo Park. The black color of Hyun Eui as a ceremonial dress of man symbolizes Heaven and Virtue. The yellow color of Whang Sang as a ceremonial dress of man symbolizes the Earth and the Impartiality. The blue or black decoration line over white ground of Sim Eui as ordinary dress of man symbolizes also Filial Piety. In woman ordinary upper garment, So Eui, black texture edging with blue line implies the mutual symmetricity with her husband's. Besides, white color texture lining So Eui symbolical to a Devine Nature and Homage implies also the deep concealment of feminine body. The black ground color of child dress "Chi Po Eui" symbolizes Naivety, and the red silk color of it's decoration line, belt and tress ornaments implies the praise of the Virtue & Learning and also "Expel the Evil" of our traditional national characteristics. As described above the meaning and symbolic characters about the color and style of clothes appearing at "GER GA JAP BOK GO" has a very Chinese disposition, but it's author Kyu Soo Park modified somewhat to be in harmony with the real social situation of our Country during that latest stage of Yi Dynasty, because he was one of the prominent pragmatist at that time.

• 복식
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• 제64권7호
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• pp.143-155
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• 2014

This study focuses on Yusam, a military raincoat that was worn during the Joseon Dynasty. The purpose of this study is to review the types and management system of Yusam. Documentary records, paintings and relics were used as research materials. Yusam was recorded as either Yusam(油衫) or Yu-ui(油衣) in writing. It usually looked like a skirt and was worn like a cape, but there were differences in length. Some of them took the form of a short coat with half-sleeves and side slits. Research analysis results of Silrok, Ilseongrok and the archives of the military camp in the later Joseon are as follows: First, Mokyusam and Jiyusam coexisted as military raincoats. Mokyusam was made with cotton and perilla oil, while Jiyusam was made with traditional Korean paper, a cotton edging and perilla oil. Second, the differences between general Yusam and military Yusam include the material of the clothing, the materials for waterproofing, the color, and the manufacturer. Third, each military camp supplied soldiers with hundreds to thousands of Yusam. Military officers and King's guards wore Mokyusam because Mokyusam was higher than Jiyusam. Fourth, soldiers Yusam together with Yujeongeon, Chorip, Galmo, or Hwihang as a hat. Fifth, the higher the rank, the higher the price of Yusam and the longer the term of usage. On the other hand, as the rank got higher, the cost of the supplementary oil rose, while the duration of usage got shorter.

• 한국운동역학회지
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• 제20권3호
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• pp.319-325
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• 2010

The purpose of this research was to investigate the differences in the ski carving turn motion according to level of expertise. The posture and movement of 6 skiers nearby the fall-line was evaluated with a biomechanical approach focusing the rotational mechanics. The slope was at an angle of $9^{\circ}$ and the following variables were measured and calculated: tangential velocity, change of COM height after passing fall-line, width between feet, angle between upper body and thigh, trunk angle, average radius of curvature and average centripetal force. The expert skiers minimized their center of mass height movement and maintained the width of between their feet after the passing the fall-line in comparison with the beginners and intermediate skiers. The experts restrained themselves from pushing their upper body downward after the turn to maximize the centripetal force. The experts in comparison with the beginners and intermediate skiers during the turn didn't have to reduce their radius of curvature to maintain a high centripetal force. It was concluded, that the most important factor affecting the centripetal force, was for the beginners and intermediate skiers, to minimize their movement while using the appropriate amount of edging.

• 한국전자파학회논문지
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• 제22권6호
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• pp.605-612
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• 2011

본 논문에서는 차량 앞유리에 탈부착이 가능한 다이폴 형태의 T-DMB 수신용 안테나를 설계하였다. 안테나의 구조는 동박과 급전선의 매우 간단한 구조를 가지며, 운전자의 시야에서 완벽히 벗어날 수 있도록 차량 유리의 테두리 쪽에 존재한다. 차체의 특성과 안테나의 입력 임피던스 특성을 고려하여 제안된 미앤더 형태의 다이폴 안테나는 T-DMB 주파수 대역(174~216 MHz)을 만족한다. Common Mode Stub를 추가한 Flexible 안테나는 차량 앞유리에서 부착되는 위치에 상관없이 안테나의 입력 반사 손실은 -5 dB 이하를 가지는 것이 가장 큰 특징이다.

• 한국운동역학회지
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• 제29권4호
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• pp.219-226
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• 2019

Objective: The purpose of this study is to provide a better understanding of short turn mechanism by describing short turns after kinematic analysis and provide skiers and winter sports instructors with data through which they are able to analyze right postures for turns in skiing in a systematic, rational and scientific manner. Method: For this, a mean difference of kinematic variables (ski-hip angle, ski-shoulder twist angle, pole checking angle, the center of gravity (CG) displacement, trunk forward lean angle) was verified against a total of 12 skiers (skilled and unskilled, 6 persons each), regarding motions from the up-start to down-end points for short turns. Results: There was no difference in a ski-hip twist angle. The ski-shoulder twist angle was large at the up-start point while a pole-checking angle was high at the down-end point in skilled skiers. Concerning the horizontal displacement of CG, skilled skiers were positioned on the right side at the upstart point. No significant difference was observed in the trunk forward lean angle. Conclusion: According to the ski-shoulder twist angle and CG horizontal displacement results, the upper body should be kept leant toward the pole. In addition, big turns should be made via edging and angulation. During pole checking, the hand holding the pole should be thrown and released toward a vector direction of the forearm.

• 지식경영연구
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• 제20권3호
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• pp.1-16
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• 2019

Jobless Growth, one of the most issue keywords for Korea's economy at this moment, stands for an economic situation where the unemployment rate once edging up at the downturn does not fall sharply even after a business cycle is on the stage of its recovery. A remarkable progress of ICT has intensified the apprehension of technology displacing human labor. A remarkable progress of ICT has intensified the apprehension of technology displacing human labor historically. Nowadays, ICT as the main cause for recent jobless growth in Korea ends up with pointing out. This study is to investigate whether the ICT leads to an economic situation of jobless growth. We served an empirical analysis using firm-level panel data from 2009 to 2013 and estimated the effects of ICT on both firm's employment and productivity. A result suggests not only does the employment increase with the rise of ICT investment, but also the employment becomes a complete mediator in terms of linking ICT and firm's productivity. It turns out to be a groundless fear that the ICT rules out human labor causing jobless growth for Korea's economy according to the result revealed.

• 한국운동역학회지
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• 제30권1호
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• pp.17-25
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• 2020

Objective: The purpose of this study is to provide a better understanding of long turn mechanism by describing long turns after kinematic analysis and provide skiers and winter sports instructors with data through which they are able to analyze right postures for turns in skiing in a systematic, rational and scientific manner. Method: For this, a mean difference of kinematic variables (the center of gravity (CG) displacement of distance, trajectory, velocity, angle) was verified against a total of 12 skiers (skilled and unskilled, 6 persons each), regarding motions from the up-start to down-end points for long turns. Results: First, concerning the horizontal displacement of CG during a turn in skiing, skilled skiers were positioned on the right side at the upstart and edge-change points at a long turn. There was no difference in anteroposterior and vertical displacements. Second, in terms of CG-trajectory differences, skilled skiers revealed a significant difference during a long turn. Third, regarding skiing velocity, skilled skiers were fast at the edge-change and maximum inclination points in long turns. Fourth, there was no difference in a hip joint in terms of a lower limb joint angle. In a knee joint, a large angle was found at the up-start point among skilled skiers when they made a long turn. Conclusion: In overall, when skilled and unskilled skiers were compared, to make a good turn, it is required to turn according to the radius of turn by reducing weight, concerning the CG displacement. Regarding the CG-trajectory differences, the edge angle should be adjusted via proper inclination angulation. In addition, a skier should be more leaned toward the inside of a turn when they make a long turn. In terms of skiing velocity, it is needed to reduce friction on snow through the edging and pivoting of the radius or turn according to curvature and controlling ski pressure. Regarding a lower limb joint angle, it is important to make an up move by increasing ankle and knee angles instead of keeping the upper body straight during an up motion.