• 한국운동역학회지
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• 제22권3호
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• pp.269-276
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• 2012

The purpose of This study's aim is to examine the difference in the changes of body segment movement, variables for ball quality, and carry at golf driver swing according to the ball quality using comparative analysis. Regarding the impact variables according to the ball quality using the track man and carry, club speed was the fastest at draw shot, ball speed was the fastest at straight shot, and smash factor was the lowest at draw shot. About the vertical launch angle, the fade shot showed the highest launch angle while the max height of the ground and ball was the highest at fade shot. And carry was the longest at draw shot. For the flight time, it was the longest at draw shot. The landing angle was the largest at fade shot. About the club head position change and trajectory, at the overall event point, the fade shot drew a more outer trajectory at the point of the follow through(E6) than the straight or draw shot. Regarding the angular speed of shoulder rotation, at the overall event point, the fade shot showed the greatest angular speed change in the follow through(E6). Also, about the angular speed of pelvic rotation, at the overall event point, the draw shot showed the greatest angular speed change at the point of down swing(E4). Concerning the stance angle change, both straight and fade shots were open as the concept of open stance whereas the draw shot was close as that of close stance. Regarding the previous study, the most important factor of deciding Ball Quality is the club face angle's open and close state at Impact. In short, the Ball Quality and carry were decided by this factor.

• 한국운동역학회지
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• 제20권2호
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• pp.239-243
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• 2010

The putting stroke accounts for 40~50% of total stroke for a golf rounding and most golfers have difficulties on the puting. Studies for the putting stroke have been conducted by analyzing various factors such as kinematics, kinetics, psychologic and physiologic parameters. A lot of devices were developed to support the studies. However there was no appropriate method to measure the position of the ball quantitatively. In this study, we developed a new measurement system to measure and evaluate the putting result. The developed system uses a USB camera to take the 2-dimensional image of the surface including the hole cup at the center of the image and the ball. The position of the ball is extracted as a set of distance and angle in polar coordinate system. We evaluated the new system with an indoor set-up for putting experiments and the system provided accurate measurement results. The proposed system can be combined with the other measurement systems such as 3D motion capture system and force plate without any restriction.

• 한국응용과학기술학회지
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• 제37권4호
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• pp.986-995
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• 2020

본 연구는 영친왕의 일본 생활과 주변 인물들과의 관계를 사회학적으로 분석하여 그 동안 알려지지 않은 골프활동을 찾는 것으로 국내 및 일본의 서적, 논문, 학회지, 신문, 각종 잡지, 사진 등의 문헌분석을 통해 다음과 같은 결론을 얻었다. 영친왕은 일본 황족 마사코와의 결혼으로 일본 황족의 대우를 받게 되어 일본 황실의 영향으로 1924년 골프를 처음 배우게 되었고, 1925년에는 일본 황태자가 개최하는 대회에도 참가하는 등의 골프활동을 보였다. 그리고 1927년에는 1년간의 유럽여행을 떠나며 싱가폴, 파리, 스위스, 영국, 벨기에, 네덜란드, 이탈리아에서 골프 경기는 물론 골프장 시찰, 골프 레슨, 골프 공 제조 공장들을 방문하며 많은 골프활동을 보였다. 유럽에서 돌아온 후에는 경성 군자리골프장 부지, 건설자금, 운영비를 지원해 주었다. 그 후 일본 고급 직업 장교로 생활하는 기간에는 특별한 골프활동을 보이지는 못하였고, 태평양전쟁 이후에는 전시 복구 등의 사회적인 여건과 경제적 문제, 1958년부터는 건강상의 문제로 더 이상의 골프활동은 찾아볼 수 없었다.

• 한국운동역학회지
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• 제17권1호
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• pp.91-97
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• 2007

The purpose of this study was to investigate the changes of various balls velocity under the different surface conditions after impact. For this study, four different balls were used which are golf ball, tang-tang ball, table tennis ball, and iron ball. And two different types of ground conditions were used which are artificial grass green and glass green. Movements of putter head and ball were recorded with 2 HD video cameras(60 Hz, 1/500s shutter speed). Small size control object($18.5cm{\times}18.5cm{\times}78.5cm$) was used in this study. To transfer the same amount of kinetic energy to the ball, pendulum putting machine was used. Analyzing the process of impact and the ball movement, a putter was digitized the whole movement but the ball was digizited within the 50cm movement. Velocities were calculated by the first central difference method(Hamill & Knutzen, 1995). Putter head velocities were about 112.2cm/s-116.2cm/s at impact. Maximum ball velocities were appeared 0.08s-0.10s after impact no matter what the ground conditions are. Table tennis ball recorded higher ball velocities than the other ball velocities and iron ball recorded the lowest ball velocity in this group. But Table tennis ball was influenced with the frictional force and immediately was decreased at the artificial grass green condition. If an object is received the kinetic energy under the static condition(v=0cm/s), the object recorded the maximum velocity shortly after the impact and then decreased the velocity because of the frictional force. The ball distance from the start position to the peak velocity position is about 6cm-10cm under the 112.2cm/s-116.2cm/s putting velocity with putter. 0.25 seconds later after impact balls were placed 40cm distance from the original position except iron ball. In this study, ball moving distances were too short therefore it was not possible to investigate the reactions after the translational force is disappeared. Rotational force would play a major role at the end of the ball movement. Future study must accept two things. One is long distance movement of ball and the other is balanced ground. Three-piece ball is a good item to investigate the golf ball movement on the different surface conditions.

• Journal of Sport and Applied Science
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• 제8권3호
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• pp.1-6
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• 2024

Purpose: This study aims to verify the effectiveness of acute anodal transcranial direct current stimulation (A-tDCS) using Halo Sport headset device on golf performance in professional golfers. Research design, data, and methodology: Eight professional golfers who voluntary participated in high-level golf tournaments were recruited in this study. They attended one single-session intervention which was stimulated by Halo Sport headset device (n=8). The A-tDCS halo sport session lasted for 20 minutes and stimulated on the motor control area of the cortex (M1). Four golf swing performance tasks (driver, iron, 100-yard shot, 50-yard shot) were performed before and after halo intervention. Key indicators of golf swing performance (Club Speed, Face Angle, Ball Speed, Smash Factor, Spin Rate, Side, Carry, Total) were collected by Trackman launch monitor. Results: In Halo session, there were no found statistical significance in driver, iron and approach (100, 50 yards) after intervention (P<0.05). Even some of variables (face angle, smash factor, carry and total distance) in driver, distance accuracy of 100 yards and direction accuracy of 50 yards were slightly improved tendency, but it was not significant (P<0.05). Meanwhile, there was any enhance all of variables in iron. Conclusions: As a result, the current study concludes that the acute A-tDCS halo sport intervention has no effect on the positive golf performance improvement for professional players. Further implications were discussed.

• 한국운동역학회지
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• 제16권1호
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• pp.43-53
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• 2006

Among several movements that occurred upon a slope, golf swing is the most typical one because environmental conditions dynamically vary with many kinds of slopes. Some studies on the golf swing were performed about a weight transfer on flatland, however, there couldn't be seen any study about the weight transfer on slope elsewhere. Therefore, the purpose of this study was to provide quantified data to objectively test the coaching words and keys about the weight transfer at sidehill slope during goal impact EspeciaIly sidehill Slopes with ball above the feet. Four highschool golfer, who have average handy 5, were recruited for this study. Plantar pressure distribution and cinematographic data were collected during golf swing in the conditions of flatland, $5^{\circ}$, $10^{\circ}$ and $15^{\circ}$sidehill slope simultaneously. The two data were used to synchronize the two data later. The plantar regions under the foot were divided into 8 regions according to the directly applied pressure pattern of the subject to insole sensor. The 8 foot regions were hullux, medial forefoot, central forefoot, lateral forefoot, medial midfoot, lateral midfoot, medial heel, and lateral heel. And the plantar pressure data was also divided into four movement address, phases-backswing. downswing, and follow-through phases according to the percentage shown to the visual information of film data. Based on the investigations on public golf books and experiences of golfers, it was hypothesized by the authors in the early of this study that the steeper slopes are, the more weight loads on left foot that positions at the higher place. When observing the results of plantar pressure and vertical force curves according to the sidehill slope conditions, the hypothesis could be accepted.

• 아시안잔디학회지
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• 제24권2호
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• pp.211-217
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• 2010

본 연구는 골프장 그린의 볼마크 수리방법 중 잔디 회복이 빠른 효과적인 방법을 규명하고자 수행하였다. 볼마크 수리방법은 대조구(볼 마크 수리 않음, A방법), 미국의 전통적 2가지 방법(USGA B방법, GCSAA C방법), 국내 골프장의 인력에 의한 3가지 방법(안성베네스트 D, 스카이72 E, 레이크사이드 F방법), 볼마크 수리기(6, 8, 14날)에 의한 3가지 방법(G, H, I방법) 등 모두 9가지 방법이 적용되었다. 공시된 그린의 벤트그래스 품종은 'Penncross', 'T-1', 'CY-2' 3품종이었다. 본 시험은 2009년 9월에서 11월까지 서울 레이크 사이드 골프장(용인시 모현면 능원리)의 nursery에서 행하였다. 전체 벤트그래스 3품종의 평균적 처리별 볼마크 회복율(%)은 E, D, C, B, F, I, H, G, A 순으로 빨랐으며 인력에 의한 볼마크 수리방법이 칼날이 부착된 수리기에 의한 방법보다 효과적이었다. 'Penncross'품종의 볼마크 회복율은 E, D, B, C, F, I, H, A, G 순으로 빨랐고, 'T-1' 품종의 볼마크 회복율은 D, E, B, F, C, H, I, A, G 순으로 빨랐으며, 'CY-2' 품종의 볼 마크 회복율은 D, E, C, F, B, H, G, I, A 순으로 빨랐다. 품종에 따른 볼마크 회복속도는 'CY-2', 'Penncross', 'T-1' 순이었다. 이상의 결과 볼마크 수리는 스카이72 골프장의 인력에 의한 방법인 '볼 마크 중앙의 피해 잔디를 포크로 제거한 후, 손으로 잔디를 두드리면서 안쪽으로 모으고 포크로 끌어당기면서 더 모은다. 둥근 나무막대로 잔디를 평탄하게 다진 후, 마지막으로 잔디에 물을 주는 방법'이 가장 효과적인 볼마크 수립방법으로 나타났다.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2017년도 제55차 동계학술대회논문집 25권1호
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• pp.5-6
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• 2017

본 논문에서는 초고속 카메라가 아닌 일반 산업용 카메라를 이용하여 기존의 초고속 카메라와 비슷한 성능을 가진 골프 시뮬레이터 시스템을 개발하였다. 골프공 인식 카메라의 특성에 관하여 분석하였고, 사용하는 조명의 특성을 비교하여 카메라특성에 맞는 할로겐 램프를 사용한 조명장치를 설계 제작하였다. 영상처리 알고리즘을 이용하여 공의 속도, 방향, 높이 및 스핀을 계산하여 모니터에 디스플레이 하였다. 또한 게임 프로그램적인 요소를 반영하여 실제 데모용 키오스크 시스템을 구현하였다.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2006년도 한국컴퓨터종합학술대회 논문집 Vol.33 No.1 (B)
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• pp.88-90
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• 2006

체감형 가상현실 스크린 골프 게임 개발에 필요한 도구로 골프 공의 궤적과 속도를 실시간으로 표시하고 분석하는 시뮬레이터를 설계하고 구현하였다. 현실감 있는 골프 공의 움직임을 표현하려면 현실 세계와 동일한 물리 법칙을 적용하여 실시간으로 표현하고, 물리적인 요소들이 올바르게 적용되었는지 관찰하고 분석해야 할 필요성이 있다.

• 실천공학교육논문지
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• 제14권2호
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• pp.235-244
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• 2022

본 연구는 상용 제품인 골프공디스펜서의 공학설계를 주제로 하는 기계공학 교과목 개발 및 운영 사례를 제시하고 있다. 교과목은 김종원과 W. Beitz가 제안한 체계적인 공학설계 방법에 따라 수행되었다. 이 방법은 공학설계를 크게 '제품기획 → 개념설계 → 기본설계 → 상세설계'의 4단계로 나누고 있으며, 특히 개념설계 단계를 '기능구조도→세부기능에 대한 동작원리 탐색 → 다양한 설계대안 창안 → 최적설계대안 선정'으로 구분한다. 개념설계에서는 골프공디스펜서의 입출력을 정의하고 이에 대한 기능구조도를 작성한다. 이 과정을 통해 제품의 기능을 세분화하고 각각의 동작원리를 체계적으로 탐색할 수 있다. 또한 다양한 동작원리를 조합하고 이를 평가하여 최적설계대안을 도출한다. 기본설계에서는 고장모드 분석을 통해 시제품 레이아웃을 완성하고 이를 활용하여 실제 시제품을 제작하고 성능을 평가한다. 이상과 같은 과정을 통해서 수업에 참여한 학생은 상용제품을 체계적인 방법으로 설계해보고 시작품까지 제작해보는 경험을 기계공학과 교육과정 내에서 해볼 수 있을 것이다.