• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.1
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• pp.83-90
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• 2008

Taekwondo is a martial art form and sport that uses the hands and foot for attack and defense. Taekwondo basic motion is composed of the breaking, competition and poomsea motion. In the side kick among the competition motion, the impact force is larger than other kinds of kicks. The side kick with the front foot can be made in two steps. In the first step, the front foot is stretched forward from back stance free-fighting position. For the second step, the rear foot is followed simultaneously. Then, the kick is executed while entire body weight rests on the rear foot. In this paper, impact analysis of the human model for hitting posture is carried out. The ADAMS/LifeMOD is used in hitting modeling and simulation. The simulation model creates the human model to hit the opponent. As the results, the dynamic analysis of human muscle were presented.

• Korean Journal of Applied Biomechanics
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• v.13 no.1
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• pp.155-171
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• 2003

The purpose of this study was to analyze the kinematic variables of over head kick(OHK) in soccer with three dimensional analysis technique and show the kinematic characteristics of it. The 7 subjects were university football player who have been playing football more than 7 years. The OHK was filmed on 16mm video camera(30frame/sec.) kinematic variables were temporal, postures, and COG(center of gravity). The mean values and the standard deviation for each variables were obtained and used as basic factors for examining characteristics of OHK. The results of this analysis were as follows : Temporal variables : The total time elapsed(TE) of OHK was $0.95{\sim}1.14sec$, the 1st phase was 0.35sec., 2nd phase was 0.46sec., and 3rd phase was 0.22sec.. Posture variables : When subjects performed OHK at the impact event, the ankle and knee angle of kicking foot were more extend than supporting foot. but the hip angle of supporting foot were more extend than kirking foot. Moving distance of the center of mass of the both foot. When subject performed OHK at the impact event, the range of distance on mediolateral direction aspect into right left shoulder line, anteroposterior direction aspect was $20.9{\pm}10.5cm$, vertical direction aspect was $92.3{\pm}19.9cm$. Angular velocity : the faster angular velocity of knee ankle on the kicking foot pew form jump position to landing position, the faster velocity of ball became. C. O. G. variables. When subject performed OHK at the impact event, upper part of the body was getting lower, lower part of the body was getting higher.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.523-526
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• 2002

In the bearing wall systems, a form work has a lot of room that saves cost because it takes a substantial proportion of construction cost. Therefore the systemic and efficient methods are required in the form work. This study focuses on methods that enhance the quality and the productivity of form work and presents the kicker form as an alternative plan to simplify the form work through being modular and automatical it. Work sampling method is used for productivity measurement. It is expected that it will reduce the work process and improve the Qualify and the podructivity of construction.

• Korean Journal of Applied Biomechanics
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• v.16 no.3
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• pp.173-181
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• 2006

The purpose of this study is grasp the problem of the gymnast, Kim, Dong-Hwa's Kip to Swallow Motion in Rings, and make up for the weak points to help him to perform a better performance. Therefore, two tryouts for $28^{th}$ Athens Olympic Games were filmed using video camera then finalized with Kinematical Analysis using 3D motion analysis program followings are the form of conclusions. 1. In the very first tryout, when he was doing a Swallow Support Scale, his CM position was high and arm slope was deduction because when he was doing Kip, the ascent velocity was low and he tried excessively to pull him on rings due to relying upon angular movement of shoulder joint. 2. When he was doing drop, he let his hip angle bend only little bit and let fall so making shoulder angle wider and maintain the level horizontally occurs strong drop motion when vertical descent is happening. 3. As a result, lowering the direction of a kick makes CM's movement path lower, increase vertical ascent velocity, and it helps to do the Swallow Support motion in short period of time. 4. After a strong drop motion, which is deep and fast, would make rope of ring shake so there is a defect that the body moves to forward area. However, it does not effect in Swallow Support Scale motion. 5. In the second tryout, trunk rotation angle and arm slope was fixed decrease while doing rotary motion. When rotary motion was happening, before the body was going under the rings, maintained his arm slope horizontally so his Swallow Support Scale motion was nearly perfect.

• Aerospace Engineering and Technology
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• v.8 no.2
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• pp.83-91
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• 2009

This paper concerns the dynamic property of TVC system in the upper stage of KSLV-I. The minimum bandwidth of TVC system is predicted by gathering and comparing the dynamic test data through whole development phases of KSLV-I. The linear models which approximate the dynamic data are also suggested. It is shown that the minimum bandwidth of KSLV-I TVC system is guaranteed over 6.0 Hz at one degree command. It is also shown that the linear model of KSLV-I TVC dynamics takes the form of the transfer function with an 8-th order denominator and a 2-nd order numerator. These results will play an important role in analyzing the flight stability and performance of KSLV-I.

• Korean Parent-Child Health Journal
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• v.5 no.2
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• pp.206-223
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• 2002

The purpose of this study was to discuss the nature of pregnancy experience among unwed Korean mothers and to figure out what it meant for them, by asking some of them to reflect on themselves in a written form from interpretative and phenomenological perspective, based on van Manen's research method of the same approach. The subjects in this study were seven unmarried mothers in Korea. The data were collected from July through December 2000 through in- depth interview and observation. The statements of the participants were taped, recorded, analyzed and select essential themes. To have a phenomenological understanding of the pregnancy unmarried mothers, literary works, including essays and novels, were reviewed. The findings of this study were as below: The selected substantial themes about the pregnancy and birth experiences of the single mothers included 'hatred for boy friend,' 'hatred for the fetus,' and 'hatred for myself.' The unmarried mothers met their boy friends through the introduction of friends. At first, they were good friends, but they soon went on a date and had sexual relation with no common knowledge about sex. Most of them were aware of their pregnancy after they felt fetal movement, but they put off taking the test because they didn't want to accept the fact and feared it. Such an attitude was rare among married pregnant women, and being pregnant with no prior preparation or sexual knowledge is not common in Western countries. They felt guilty and informed their boy friends of the fact, but the boy friends didn't admit their responsibility and rejected the babies. This made the poor girls hate them, and it turned into severe abhorrence. They thought their lives were ruined by the babies, and wished they would disappear. They reproached the babies, hitting their own bellies or making a kick. They considered themselves to be abandoned and didn't want to live any more. Giving themselves up to despair, some attempted to commit a suicide. They hoped to die, thinking their death would solve the problem. When they lost a chance of abortion and were about to have the babies adopted, they felt sorry for them. The unwanted pregnancy gave them a pain, but they keenly felt they were loved by their mothers, and learned the value of family. It's attempted in this study to clearly show how much unmarried Korean mothers suffered from pregnancy, and this effort paved the way for seeing unwed mothers in a new light and having a better understanding of them, instead of sticking to general perception.