• 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.

• Korean Journal of Applied Biomechanics
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• v.26 no.4
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• pp.377-382
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• 2016

Objective: The purpose of this study was to provide data on gait characteristics of K-pop professional dancers. Method: Participants were divided into four groups: male dancers (n=10, age: $28.2{\pm}3.4years$, height: $175{\pm}6cm$, weight: $68.9{\pm}5.6kg$), female dancers (n=10, age: $26.7{\pm}3.1years$, height: $162{\pm}4cm$, weight: $52.1{\pm}3.7kg$), non-dancer males (n=10, age: $25.2{\pm}2.6years$, height: $171{\pm}6cm$, weight: $66.4{\pm}5.3kg$), or non-dancer females (n=10, age: $26.2{\pm}3.0years$, height: $161{\pm}5cm$, weight: $56.4{\pm}6.7kg$). Twelve infrared cameras (Qualisys, Oqus 500, Sweden, 150 Hz.) were used to capture three-dimensional motion data. Gait motion data of professional dancers and ordinary persons were obtained. Results: K-pop dancers' dynamic stability during the female toe off event and the male heel contact event was better compared with that of ordinary persons in the front-rear direction. In addition, the results showed a significant difference in the margin of stability (MoS). However, the medial-lateral direction of both female and male dancers during heel contact and the toe off event was more stable compared with ordinary person, who exhibited an increased MoS than did the dancers. Conclusion: This study aimed to investigate the gait characteristics of K-pop professional dancers in comparison with ordinary persons using gait parameters and MoS. The stability of K-pop professional dancers' dynamic gait in the front-rear direction was better than that in the medial-lateral direction. Therefore, further studies in which the dance movements of K-pop dancers are sub-divided and analyzed will be necessary to reduce related injury.

• Korean Journal of Applied Biomechanics
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• v.13 no.1
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• pp.139-153
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• 2003

The purpose of the study was to present technical guidance about the field goal kicking motion in American football for novices. For this purpose, kinematic analysis on the field goal kicking motion of two skilled players and two unskilled players was carried out. The following conclusions were made: 1. In comparison on the total elapsed time of the kicking, there were no significant differences between two groups. The progressing time from BP event to impact among experts group, however, took 0.141 second less than that of novices group. 2. The experts group showed right hip rotatier horizontally toward the targeted ball fixing left hip as the axis. On the other hand, the novices group didn't use the left hip as the axis in the kicking motion. 3. At the impact of kicking the ball, regarding with the distance of the ball and the supporting leg, the right and left distance of experts was 3.45cm longer than that of novices, the front and the rear distance of experts was 5.14cm shorter than novices. 4. At the impact, experts' initial velocity of the targeted ball was $5.27^m/s$ faster than novices', besides experts' incidence angular displacement was $3.78^{\circ}$ larger than novices'. 5. After BP event, experts showed a stable movement maintaining flexion and extension at left hip joint and knee joint. On the other hand, for novices, the angle of the left lower extremities became larger. 6. Experts showed the efficient flexion and extension of the hip joint and the knee joint during following procedure in the whole event of the kicking motion. At the BP event, the right knee joint angle of novices was $11.46^{\circ}$ larger than that of experts. However, the duration of the impact event and FT event among, novices had less extension of knee joint than experts. 7. At the 2nd phase, for both of the groups, the angular velocity of the knee joint drastically increased as the angular velocity of hip joint decreased. However, only novices showed the largest negative angular velocity at the impact.

• Korean Journal of Applied Biomechanics
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• v.20 no.1
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• pp.25-32
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• 2010

This study was performed to investigate the kinematic factors on the head hitting motion based on weight change of bamboo swords in kumdo. The kinematic factors, needed time per phase, COB displacement and velocity, angle(wrist, elbow, shoulder joint, hip joint, knee joint), were analyzed by the 3-D motion analysis method against 6 male middle school athletes. The results were as follows. 1. The needed time of head hitting motion based on weight change of bamboo swords was shorter when weight was heavier. 2. The COB displacement of left/right was bigger when weight was heavier. the displacement of right foot was higher at backswing phase and impact phase when weight was heavier and at impact time when weight was lighter. 3. The COB velocity was faster at impact time when weight was heavier, the velocity of sword tip was fastest for each event with bamboo sword weight of 440 g. 4. The angle of left elbow was smaller at top of backswing and impact when weight was heavier, the angle of left shoulder was bigger when weight was heavier, the right knee angle was biger at start when weight was heavier, at impact when weight was lighter.

• Korean Journal of Applied Biomechanics
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• v.17 no.2
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• pp.61-73
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• 2007

The purpose of this study was to investigate the influence of the muscular endurance on the kinematic factors during a prolonged run. Subjects, 12 males, who were divided into three groups(lower group, general group, and in higher group) after measuring the lower limb's muscular endurance previously. They were asked toe run on the treadmill at 7.4km/h of speed. To analyze the kinematics parameters of the trunk during running, the ProReflex MCU Camera(Qualisys, Sweden) were used. All parameters were sampled from 5 minute, 40 minute, and 60 minute moments during running. An ANOVA with Repeated Measure was used to test the statistic significance between and within groups for all parameters determined with SPSS 11.0. Significance was defined as p<.05. The conclusions were as follows; There was significantly difference within(lapse of running time) groups in the take-off and minimum knee angle event of swing phase of the trunk flexion and extension. In conclusion, the muscular endurance affected on movement of the trunk during a prolonged run. In addition, it showed that there was significant difference in the energy consumption by lapse of running time. Therefore, it seems to be relationships between the muscular endurance and running efficiency.

• Korean Journal of Applied Biomechanics
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• v.30 no.3
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• pp.235-245
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• 2020

Objective: The purpose of this study was to investigate the differences between visual search, eye fixation positions, and eye fixation position on whole body regions while judging final matches of dance sports. Method: Ten experienced judges (male 6, female 4) and six dance sports couples belonging to the top Korean leagues in the Korea Dance sports Federation were participated. Wearable eye trackers were used for data collection. The independent t-test was conducted to examine the effects of gender, and the two-way ANOVA was conducted to examine the effects of judges' gender, dance event, and ranking. Results: It was found that the movement of male contestants was preferred, and the gaze fixation was high for torso movements in the judges' evaluations. Moreover, attention was focused on the upper body rather than the lower body; this was maintained for about seven seconds to evaluate each couple. Conclusion: This find was the relative comparison between the two couples was the determining factor in winning or losing.

• The Journal of the Korea Contents Association
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• v.7 no.10
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• pp.262-273
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• 2007

The current study sought to acknowledge the female sport fan as a sport marketing segment. In order to do so, female sport consumption motivation was identified and among motivation factors, factors effecting re-attend intention and word of mouth intention according to level of team identification was identified. In order to accomplish the purpose a focus group interview was conducted concerning female sport fans, and a survey took place in Korean Pro-sport event collecting 300 data. Among 300 data 248 data were used for the analysis. Using Lisrel 8.7 and SPSS 15.0 correlation analysis, descriptive analysis, confirmatory factor analysis, and multiple regression analysis was conducted. The results of study are as follows, First, 9 female sport consumption motivation was identified and among these factors, skill, achievement, drama, and escape had a positive effect on re-attend intension. Second, among 9 female sport consumption motivations skill, achievement, and social factor had a positive effect on word of mouth intention. Third, among the motivation factors, factors effecting re-attend intention had difference on the level of team identification. Forth, among the motivation factors, factors effecting word of mouth intention had difference on the level of team identification.

• Journal of Korea Multimedia Society
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• v.7 no.11
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• pp.1540-1549
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• 2004

In this paper, we propose an algorithm to detect semantic events in golf video using Hidden Markov Model. The purpose of this paper is to identify and classify the golf events to facilitate highlight-based video indexing and summarization. In this paper we first define 4 semantic events, and then design HMM model with states made up of each event. We also use 10 multiple visual features based on MPEG-7 visual descriptors to acquire parameters of HMM for each event. Experimental results showed that the proposed algorithm provided reasonable detection performance for identifying a variety of golf events.

• Korean Journal of Applied Biomechanics
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• v.15 no.3
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• pp.117-132
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• 2005

It was to study a following research of "A Kinematic Analysis of Air-rolling-breakfall in Judo". The purpose of this study was to analyze the Center of Gravity(COG) variables when performing Air-rolling-breakfall motion, while passing forward over(PFO) to the vertical-hurdles(2m height, take off board 1m height) in judo. Subjects were four males of Y. University squad, who were trainees of the demonstration exhibition team, representatives of national level judoists and were filmed by four 5-VHS 16mm video cameras(60field/sec.) through the three dimensional film analysis methods.COG variable were anterior-posterior directional COG and linear velocity of COG, vertical directional COG and linear velocity of COG. The data collections of this study were digitized by KWON3D program computed The data were standardized using cubic spline interpolation based by calculating the mean values and the standard deviation calculated for each variables. When performing the Air-rolling-breakfall, from the data analysis and discussions, the conclusions were as follows : 1. Anterior-posterior directional COG(APD-COG) when performing Air-rolling-breakfall motion, while PFO over to the vertical-hurdles(2m height) in judo. The range of APD-COG by forward was $0.31{\sim}0.41m$ in take-off position(event 1), $1.20{\sim}1.33m$ in the air-top position(event 2), $2.12{\sim}2.30m$ in the touch-down position(event 3), gradually and $2.14{\sim}2.32m$ in safety breakfall position(event 4), respectively. 2 The linear velocity of APD-COG was $1.03{\sim}2.14m/sec$. in take-off position(event 1), $1.97{\sim}2.22m/sec$. gradually in the air-top position(event 2), $1.05{\sim}1.32m/sec$. in the touch-down position (event 3), gradual decrease and $0.91{\sim}1.23m/sec$. in the safety breakfall position(event 4), respectively. 3. The vertical directional COG(VD-COG) when performing Air-rolling-breakfall motion, while PFO to the vertical-hurdles(2m height) in judo. The range of VD-COG toward upward from mat was $1.35{\sim}1.46m$ in take-off position(event 1), the highest $2.07{\sim}2.23m$ in the air-top position(event 2), and after rapid decrease $0.3{\sim}0.58m$ in the touch-down position(event 3), gradual decrease $0.22{\sim}0.50m$ in safety breakfall position(event 4), respectively. 4. The linear velocity of VlJ.COG was $1.60{\sim}1.87m/sec$. in take-off position(event 1), $0.03{\sim}0.08m/sec$. gradually in the air-top position(event 2), $-4.37{\sim}\;-4.76m/sec$. gradual decrease in the touch-down position(event 3), gradual decrease and -4.40${\sim}\;-4.77m/sec$. in safety breakfall position(event 4), respectively. When performing Air-rolling-breakfall showed parabolic movement from take-off position to air-top position, and after showed vertical fall movement from air-top position to safety breakfall. In conclusion, Ukemi(breakfall) is safety fall method Therefore, actions need for performing safety fall movement, that decrease and minimize shock and impact during Air-rolling-breakfall from take-off board action to air-top position must be maximize of angular momentum, and after must be minimize in touch-down position and safety breakfall position.

• Journal of the Korea Society of Computer and Information
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• v.25 no.8
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• pp.99-109
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• 2020

What sports have in common is that they must use their bodies to play and lead to victory. The use of the body differs in many ways depending on the event, which part should be used as the focus. The commonality of all sports is that sports can achieve the best results by using and using parts of the body in harmony. The use of strength or muscles varies depending on the type of sport or the type of sport, so the use of the body or the results of athletic events also varies. Sports are premised on the organic use of the body, but the implications of sports can be found in that the degree of organic use does not apply equally to all sports. Sports demand organic balance and flexibility. Depending on the type of sport, you can explore which organic harmony produces more effective effects and find out which events are more beneficial to the human body. This study aimed to find out whether the organic harmony of the body actively contributes to the development of sports and a healthy mental culture. In this study, we proposed the hypothesis that the modern Pentathlon will induce the most desirable organic harmony as a global Olympic sport, and tried to verify that the hypothesis is valid and verifiable. In order to do this study, I tried to find out the organic viewpoints centered on the Miletos school, re-examine the meaning of the modern Pentathlon of games as an Olympic event, and conduct organic harmony and exploration of the modern Pentathlon of games in terms of sports.