• 한국운동역학회지
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• 제19권2호
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• pp.323-336
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• 2009

본 연구는 골프스윙의 교육방법 중 현장지도를 위한 과학적 근거와 보조 자료의 필요성을 알아보기 위해 실시되었다. 따라서 숙련자인 투어프로골퍼를 대상으로 드라이버스윙의 현장지도 결과를 운동학적 관점에서 재해석하고 정밀한 분석을 통해 현장지도의 타당성과 오류를 검사하는 하나의 예를 만들어보고자 하였다. 그 결과 현장지도결과는 운동학적 기술 분석의 정성적 평가와 대상자간과 항목간에서 약간의 차이를 나타냈으며, 결국 본 연구의 5명의 대상자가 보이는 오류의 진단은 두 방법간에 약간의 차이는 있었다. 하지만 오류의 원인과 오류를 막기 위한 보상작용의 발견에 있어서 큰 차이를 보였다. 오류의 진단은 지도자의 경험에 의해 거의 대부분 가능했다. 따라서 지도자의 경험에 의한 오류 수정을 위한 피드백은 운동학적 기술 분석의 정성적 평가와 차이를 나타냈다. 결론적으로 정확한 골프스윙의 지도에 있어서는 현장지도에 의한 즉각적인 피드백과 근본적인 원인을 정확하게 판단할 수 있는 운동학적 기술 분석의 정성적 평가가 필요하다고 사료된다.

• 한국운동역학회지
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• 제18권3호
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• pp.43-80
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• 2008

본 연구는 투어중인 프로골퍼를 대상으로 시즌 중 사용하는 드라이버스윙을 분석하는데 목적을 두었다. 연구대상으로서 3명의 KPGA(Korean Professional Golfer Association)의 투어골퍼를 대상으로 시즌중의 드라이버스윙을 수집하기위해 시즌 마지막 경기 직후 측정하였다. 다운스윙구간을 분석구간으로 정했으며 임팩트 이후 릴리즈 구간까지 분석하였다. 그 결과 기존의 운동학적 연구에서 나타난 주동분절 간의 유기적 작용은 본 연구에서도 같게 나타났다. 흉곽, 왼팔 그리고 손으로 이어지는 시스템은 상위분절인 흉곽이 먼저 움직이고 왼팔, 왼손과 클럽으로 이어지는 순서를 보임으로서 선행연구와 같게 나타났다. 오류의 수준이 크게 줄어든 데이터를 이용하여 미세한 변화를 정확하게 기술 할 수 있었다. 그러나 선행연구와 다른 결과도 나타났다. 3명의 대상자 모두에게서 왼팔의 코킹각의 구성에 있어서 기술되지 못했던 왼손의 내전각을 표현할 수 있었고 그로인해 왼손의 내전각은 코킹의 형성에 크게 영향을 주지 않는 것을 발견했다. 또한 선행연구에서 강조되었던 임팩트 직전 흉곽의 운동이 볼의 진행방향의 반대가 아니라 미세하지만 볼의 진행방향과 같은 방향으로 진행됐음을 알 수 있었다.

• 한국운동역학회지
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• 제19권2호
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• pp.273-286
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• 2009

본 연구는 고등학교 여자선수들을 대상으로 3차원 영상분석을 이용하여 스윙시 나타나는 각 신체분절 및 클럽의 직임을 운동학적 및 운동역학적 변인들을 산출하여 성공과 실패시에 대한 중요변인들을 비교 분석함으로써 정량적 자료의 추출과 더불어 정성적 평가를 하는데 목적이 있다. 운동학적 변인으로써 위치변화, 속도, 각도에 대한 3차원 분석과 지면반력에 대한 분석을 하였다. 그 결과 스윙시 클럽헤드는 어드레스와 톱스윙시 전후 이동(X축)이 매우 적게 나타남으로써 안정적 스윙이 유지 되는 것으로 나타났다. 또한 좌우방향(Y)의 신체중심이동속도는 성공적인 스윙 동작 시 실패동작시보다 임팩트시 매우 빠른 속도를 나타냄으로써 운동량 증가에 많은 기여를 하였으며 코킹각은 톱스윙에서부터 임팩트까지의 성공시가 코킹각을 더 크게 풀어 줌으로써 임팩트시 선속도 증가에 영향을 주어 비거리 증가에 유리하게 작용할 것으로 판단된다. 지면반력(GRF)은 전후방(X축)과 좌우방향(Y축)에서 안정적인 지지율로 나타남으로써 성공적 스윙으로 연결된 것으로 나타났다.

• 한국운동역학회지
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• 제25권1호
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• pp.11-19
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• 2015

Objective : The purpose of this study was to analyze the correlation between physical factors (X-factor, X-factor stretch) and club factors (club speed, ball speed, club path, smash factor, vertical launch angle, spin rate, flight time, total length) during impact and it affect on the total distance of the ball during a golf driver swing. Background : There were not enough studies that analyzed the correlation between physical factors(X-factor, X-factor stretch) and club factors(club speed, ball speed, club path, smash factor, launch angle, spin rate, flight time, total length) during a purpose swing to increase total distance. Method : For this study, 9 right handed professional male golfers (KPGA) were chosen. The test subject group used their own drivers and each took a total of 10 swings. These swings consisted of 5 purpose swings to increase total distance and 5 normal swings. Results : The purpose swing to increase total distance showed larger physical factors(X-factor, X-factor stretch) compared to a normal swing however the results were not statistically significant. Total distance increased during a purpose swing as a result of ball and club speed. Conclusion : The results showed that club factors, ball speed and club speed contributed the most in affecting the total distance of the ball during a purpose swing.

• 한국환경복원기술학회지
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• 제6권6호
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• pp.1-13
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• 2003

This study aims at conducting an awareness survey of three parties, namely, citizens, government officials, and developers for improvement of urban landscape and, based on the survey result, to suggest a direction to develop a landscape plan for improvement of urban landscape of Yong-in city in the future. The summary of this study is as follows. First, in case of Yong-in, the main drivers of forest landscape destruction were "residential complexes developed for apartment buildings" and "golf courses", the driver of river landscape damage was "the status of cleanliness of riverside and poor facilities", the driver of roadside landscape damage was "construction sites" that completely eliminate original natural landscape in both citizen and government official groups. When granting development-related approvals in the future, appropriate actions should be prepared such as developing a landscape management guideline or including a landscape plan in advance to assure plans and designs fully reflecting landscape. Second, citizens' commitment to participate in urban landscape creation and improvement was rated high at even willing to tolerate regulations including restriction of property rights. In the future, landscape improvement programs allowing resident participation should be developed proactively. The roles of government officials include preparing various criteria at a city level and convincing and guiding citizens to initiate landscape improvement project together with citizens and developers through proactive efforts by government officials. Third, the role of developers would be to realize development projects conserving local environment and/or harmonizing with local natural environment before preparing a development plan or launching construction rather than offering various considerations after executing development projects.

• 한국정밀공학회지
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• 제26권6호
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• pp.74-80
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• 2009

Path tracking of unmanned vehicle is a basis of autonomous driving and navigation. For the path tracking, it is very important to find the exact position of a vehicle. GPS is used to get the position of vehicle and a direction sensor and a velocity sensor is used to compensate the position error of GPS. To detect path lines in a road image, the bird's eye view transform is employed, which makes it easy to design a lateral control algorithm simply than from the perspective view of image. Because the driving speed of vehicle should be decreased at a curved lane and crossroads, so we suggest the speed control algorithm used GPS and image data. The control algorithm is simulated and experimented from the basis of expert driver's knowledge data. In the experiments, the results show that bird's eye view transform are good for the steering control and a speed control algorithm also shows a stability in real driving.

• 한국운동역학회지
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• 제17권2호
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• pp.31-40
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• 2007

Proper weight shifting is essential for a successful shot in golf swing and this could be described by means of the ground forces between the feet and ground. It is assumed that the ground forces would different according to the club used because the length and swing weight of each club is different. But, in present, it is not clear what changes are made by the change of clubs and this affect the swing motion. Therefore this study focused on the investigation of the changes of the ground forces and ground reaction forces (GRF) by the change of club length. The subjects were three professional male golfers. Four swings (driver, iron 3, iron 5, and iron 7) for each subject were taken by two high speed video cameras and two AMTI force platforms were used to measure the GRF simultaneously. Kwon GRF 2.0 and Mathcad 13 software were used to post processing the data. Changes of the three major component of GRF (Vertical, lateral, anterior-posterior force) at 10 predefined events were analyzed including the maximum. Major findings of this study were as follows. 1. Vertical forces; - There were no significant changes until the top of backswing. - Maximum was occurred at the club horizontal position in the downswing for both feet. The shorter club produced more maximum forces than longer ones in the left foot, but reverse were true for the right foot. - Maximum forces at impact shows the same patterns. 2. Lateral forces; Maximum was occurred at the club horizontal position for both feet, but there were no lateral forces because the direction of two forces was different. Maximum force pattern by different clubs was same as the vertical component. 3. Anterior-posterior forces; - This component made a counter-clock wise moment about a vertical axis located between two foot until the club vertical position was reached during the backswing, and reverse moment were produced when the club reached horizontal at the downswing. - Also this component made a forward moment about a horizontal axis located in the CG during the fore half of the downswing, and a reverse moment until the club reached vertical at the follow through phase. Maximum was occurred at the club vertical in the downswing for both feet. The longer club produced more maximum forces than shorter ones for both feet.

• 한국운동역학회지
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• 제19권3호
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• pp.557-566
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• 2009

본 연구에서 KPGA소속 프로골퍼 5명, KLPGA소속 프로골퍼 5명 총 10명을 대상으로 골프 드라이브 스윙시 내측광근, 외측광근, 전경골근, 비복근의 근전도 분석을 통하여 운동역학적 요인을 비교분석하였으며, 그 결과 다음과 같은 결론을 얻었다. 성별에 따른 근 활동전위 차이는 어드레스부터 백스윙탑까지 구간에서 남성의 오른쪽 비복근이 가장 높게 나타났고, 백스윙탑에서 임팩트까지 구간에서 여성의 오른쪽 전경골근이 가장 높게 나타났으며, 모든 구간과 국면에서 남성의 경우 왼쪽 하지근이 주동근이었고, 여성의 경우 오른쪽 하지근이 주동근으로 나타났으며, 통계적으로 유의한 차이가 있는 것으로 나타났다. 남자의 경우 백스윙탑에서 임팩트 구간까지 체중을 이동시키면서 왼쪽 전경골근이 주동근으로 활동하는 것으로 판단되며, 여성의 경우 오른쪽 무릎을 왼쪽 무릎 쪽으로 밀어주는 동작에서 오른쪽 외측광근과 전경골근이 주동근으로 나타났다. 따라서 남성의 경우 왼쪽 외측광근과 전경골근을, 여성의 경우 오른쪽 외측광근과 전경골근을 발달시킬 수 있는 트레이닝을 수행한다면 비거리와 방향성을 향상시킬 수 있을 것으로 판단된다.

• 한국운동역학회지
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• 제25권2호
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• pp.149-155
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• 2015

Purpose : Recently, many researchers and golf coachers demonstrated that X-factor and X-factor stretch had a co-relationship with driving distance. However, its relationship is still controversial and ambiguous. Thus, the aim of this study was to examine the relationship among X-factor, X-factor stretch and swing-related factors, including driving distance in elite golfers. Method : Seventeen male elite golfers (handicap: ${\leq}4$) with no history of musculo-skeletal injuries participated in the study. Thirty spherical retro-reflective markers were placed on including the middle point of PSIS, the right/left ASIS, the right/left lateral acromion of the scapula, driver head and shaft grip. All motion capture data was collected at 100Hz using 6 infrared cameras. Carry distance, club speed, ball speed, smash factor, launch angle, and spin rate were collected from radar-based device, TrackMan. Results : Pearson's correlation coefficient method was used to find the correlations among X-factor, X-factor stretch and swing-related factors. Positive correlations between driving distance and other swing-related factors which include club speed(r=.798, p<.001), and ball speed(r=.948, p<.001) were observed. In contrast to the swing-related factors, X-factor and X-factor stretch had no relationship to driving distance. Conclusion : These results indicate that X-factor and X-factor stretch are not key regulators in driving distance.

• 한국운동역학회지
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• 제15권3호
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• pp.71-78
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• 2005

The purpose of this research was to conduct an analysis on the factors that determine the distance at the time of target swing based on the use of late hitting of outstanding college golfers to verify the difference between late hitting and the distance that target increases in regular swing and the distance. Then, this research conducts an analysis on the correlation between club head velocity, ball velocity, launch angle, back spin, meet ratio and distance that become kinematics variables at the time of target swing. To attain the above mentioned purpose, 25 outstanding college players with average experience and handicap of 6 years and 5, respectively, were targeted Comparative analysis on two swing that target increase in regular and the distance was conducted by used driver. When it pertained to two types of swing. analysis system comprised of an analytical software called the Science Eye of the Bridgestone and peripheries was used to define the relationship between variables of club head velocity, ball velocity, launch angle, back spin, meet ratio that become kinematics variables. As for the method of processing data pertaining to the factors that determine the distance, differences of distance by the type of swing was verified by using independent T-test that leveraged SPSS 120 statistics program. Moreover, level of correlation between variables that contribute to the increase in distance through relation of correlation, and analysis of tendencies was conducted to analyze tendency of non-distance to increase in accordance to the increase of each variable. Key results produced through this experiment are as follows: 1. Artificial late hitting for increased non-distance that targets skilled players had effect on increased the distance(p<. 05). 2 The drive distance is correlated with each measured variable that is positive correlation to ball velocity, club head velocity, meet ratio and relation of back spin and launch angle are negative correlation. ball velocity and club head velocity are very high correlated with drive distance(p<.01), back spin and distance are negative correlation(p<.01). 3. Among each measured variable increasing the club velocity is the most contribution, and ball velocity and meet ratio and the increasing launch angle and back spin is negative effect for increasing distance.