• 한국조경학회지
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• 제31권1호
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• pp.66-77
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• 2003

The purpose of this study is to propose a standard putting green management program to prepare fast green suitable for international golf tournaments, and to conform whether the reported green speed model can be applied to the real field situations. The west course of Lakeside Country Club was selected for the case study. This study was initiated on August 1st, 2001 and continued through October 4th, 2001. The results are summarized as follows: 1. Following the long-term schedule, 'penncross' creeping bentgrass turf was mowed at 5.0mm(37days), 4.5mm(8days), 4.0mm(4days), 3.5mm(2days), 3.2mm(2days), 3.0mm(2days), 2.8mm(2days) and the mowing direction was changed daily. Variation of mowing height was reduced to a minimum range. Core aerification with deep tines was applied 19 days prior to the first practice round. Dry sand maintenance was top-dressed 2 times at 1.5mm/$m^2$ on the 17th day and 1.0mm/$m^2$ on the 10th day. Minimum irrigation was applied to keep the turf alive. During the tournament preparation week, dew on the putting greens was removed by using a sponge roller. Following the dew removal, the greens were cut once each morning at a height of 2.8mm. The mower used was the 21 inch working behind mower equipped with a tournament bedknife and 11 reel blades. Following the mowing, the peens were rolled with a light-weight roller in one direction in the morning. Rolling was used as a finishing technique to ensure that the surface was as smooth as possible, and to provide true ball roll and maximum green speed. In conclusion these management practices satisfied the daily green stimpmeter readings required for USGA championship play. 2. During the period of tournament preparation, no damage was observed on the green, but scalping in green edge appeared in about 0.39% of the total area of 18 greens in the west course.

• 한국운동역학회지
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• 제21권4호
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• pp.405-410
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• 2011

The purpose of this study was to compare the differences in kinematic variables and grip forces among professionals(PG), amateurs(AG), and novice group(NG) during golf putting. The participants consisted of 3 groups based on their playing ability: 8 professional golfers (handicap<5), 8 amateurs (handicap<18) and 8 novice. Each subject attempted 2.1m putts from the hole. 3D motion analysis system(Motion analysis Corp., USA) with 6 high speed cameras and grip force measurement system(Kim et al., 2007) were used to acquired kinematic and force data, respectively. To compare differences among groups, joint angles of upper limbs, trajectory and smoothness by jerk cost function(JC) of putter head and grip forces were used in this study. Results showed that there were significant differences among groups in most of variables such as joint angles, trajectory & smoothness of putter head, and distribution of grip force in both hands. In brief, we confirmed that putting stroke in PG was more accurate and smooth than that in other groups, especially NG, due to their well-controlled upper limbs and keeping grip forces constant in both hands. It can be concluded that due to skilled levels, fundamental differences of putting movement could be identified and these differences might be helpful for improving one's putting skills.

• 아시안잔디학회지
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• 제13권3호
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• pp.139-146
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• 1999

This studies was carried out to estimate the influence of mowing height, time lapse, rolling, and dew removal on green speed of putting green in Lake Side C. C. on 29, 30 Jun. 1998. The results were as follows. As mowing height increased, green speed tended to be decreased. After mowing, green speed tended to be decreased over the time, and appeared to be decrease significantly on the next day[Y=3.206-0.127.X1-1.41$\times$10-2.X4(Y=green speed, X1=mowing height, X4=time lapse)]. This suggests that the frequency of mowing must be increased to maintain the green speed. But, frequent mowing cause the turfgrass of putting green to be stressed. Rolling tended to increase green speed[Y=3.555-0.202.X1+0.111.X2(Y=green speed, X1=mowing height, X2=rolling)]. Thus, rollers is thought to be an tool used to increase green speed and rolling is expected to be able to decrease turfgrass stress while maintaining the performance level of the putting green. Dew removal appeared to increase green speed significantly[Y=2.499-0.125.X1+0.366.X3(Y=green speed, X1=mowing height, X3=dew removal)]. Thus, dew removal is expected to maintain the green speed in the morning.

• 아시안잔디학회지
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• 제26권2호
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• pp.96-101
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• 2012

Sclerotinia homoeocarpa F.T. Bennett에 의한 동전마름병은 우리나라에서 가장 흔하며 경제적으로 매우 중요한 잔디병이다. 크리핑벤트그래스로 조성된 골프장 그린에서 propiconazole, thiophanate-methyl, chlorothalonil, trifloxystrobin, boscalid를 이용하여 방제효과를 평가하였다. 또한 propiconazole과 다른 4개의 약제를 각각 혼용하여 단용처리구 대비 상승효과를 조사하였다. 동전마름병은 2개 포장의 무처리구에서 각각 평균 18.3, 66.7%의 발생을 보였다. 약제의 약효는 병 발생정도에 따라 다르게 나타났다. 살균제를 단독으로 처리하였을 때 방제 효과는 발병도가 높았을 때보다 낮았을 때 우수하였다. 처리된 살균제 중 boscalid의 효과가 가장 높았다. 살균제 혼용처리구에서는 propiconazole + thiophanate-methyl 처리구를 제외하고 단독처리구 대비상승효과가 발견되었으나, 2개 포장 모두 혼용처리구 사이에 통계적인 유의성은 발견되지 않았다. 따라서 현장에서 동전마름병 방제 시 병 발생 조건에 따라 방제전략을 달리해야 할 것으로 보여진다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권9호
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• pp.456-460
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• 2006

This paper deals with a novel autocalibration method of three-axis micromachined accelerometers applied to a new digital intelligent putter for golfers. This putter can help golfers monitor and analyze their putting posture and therefore modify their putting action to get better score and enjoy their lives through golf. The micromachined accelerometers to get information of the motion are the essential part of the putter to measure the three-axis acceleration as accurately as possible. This paper presents an efficient autocalibration algorithm to find the offset and sensitivity of accelerometers by only using the static measurement data at six different positions. The experimental results on the developed putters show the validity of the proposed algorithm for the new smart putter.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2006년도 전력전자학술대회 논문집
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• pp.302-304
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• 2006

This paper deals with a novel autocalibration method of three-axis micromachined accelerometers applied to a new intelligent putter for golfers. This putter can help golfers monitor and analyze their putting posture and therefore modify their putting action to get better score and enjoy their lives through golf. The micromachined accelerometers to get information of the motion are the essential part of the putter to measure the three-axis acceleration as accurately as possible. This paper presents autocalibration algorithm to find the offset and sensitivity of accelerometers only by using six different static measurement data. The experimental results shows the validity of the algorithm for the new smart putter.

• 한국운동역학회지
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• 제27권4호
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• pp.269-278
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• 2017

Objective: The purpose of this study was to develop a goal setting method for increasing the probability of a holed in a side inclined putting stroke. Method: Three-dimensional video data was recorded at a frequency of 120 hz per second after synchronizing 19 infrared motion capture systems (Qualisys, Gothenburg, Sweden). Putting green used a polycarbonate plate ($1.2{\times}2.4{\times}0.01meter$) with coefficient of friction (${\mu}=0.062$) and a real curve of the actual hole. Results: The velocity ratio between the club and the ball was 1:1.6 under various ball speed conditions in this study. The overall position of the break is 1 m to 1.4 m from the point where the ball leaves. If there is a slope, the ball follows the target line by the straightening force, and when it reaches 1 m position, the straightening force decreases by 30~50% and reaches to the deviation (break) point which is severely influenced by the slope. From here, the ball is aimed in a direction other than the target, and the size is affected by the slope. Conclusion: If there is a side slope, the ball moves away from the straight line, and the larger the slope, the closer the break point is to the starting point of the ball. Therefore, it is necessary to calculate the degree of departure according to the slope carefully, and it is preferable that the slower the speed is, the more the influence of the slope becomes. It is preferable to use the center of the hole as a reference when calculating the departure.

• Journal of the Korean Data and Information Science Society
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• 제24권3호
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• pp.543-555
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• 2013

이 연구는 프로골프대회에서 기록되는 중요변인들 (드라이브거리, 페어웨이안착율, 그린적중율, 센드세이브율, 리커버리율, 평균퍼팅수)이 평균타수에 미치는 영향력에 대해 집단 간 차이를 분석하였다. 구체적으로 미국남자프로골프협회 (PGA), 미국여자프로골프협회 (LPGA), 한국남자프로골프투어 (KGT), 그리고 한국여자프로골프투어 (KLPGT)에서 측정, 공개하는 자료를 통해 PGA, LPGA, KPGA, KLPGA 집단 간에 중요변인들이 평균타수에 미치는 경로에 유의한 차이가 있는지를 검증하였다. 그 결과 PGA와 LPGA 모형 간에 드라이브거리와 그린적중율이 평균타수에 미치는 경로가 p <.05 수준에서 통계적으로 유의한 차이가 있는 것으로 나타났으며, KPGA와 KLPGA 모형 간에는 드라이브거리, 리커버리율, 그리고 평균퍼팅이 평균타수에 미치는 경로가 유의한 차이가 있는 것으로 나타났다. 또한 PGA와 KPGA 모형 간에 드라이브거리, 리커버리율, 그리고 평균퍼팅이 평균타수에 미치는 경로가p <.05 수준에서 통계적으로 유의한 차이가 있는 것으로 나타났으며, LPGA와 KLPGA 모형 간에는 모든 경로에서 p >.05 수준에서 통계적으로 유의한 차이가 없는 것으로 나타났다. 이 연구 결과는 남녀 국내 투어와 미국 투어의 골프 경기력의 구조 특성을 이해하는데 필요한 기초자료로 활용 할 수 있을 것이며 향후 투어 진출을 위한 유의한 정보가 될 수 있을 것이다.

• 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.

• 아시안잔디학회지
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• 제24권2호
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• pp.161-164
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• 2010

Sclerotinia homoeocarpa F.T. Bennett에 의한 동전마름병은 북미에서 가장 흔하며 경제적으로 중요한 잔디병이다. 동전마름병을 관리하기 위해서는 봄부터 가을까지 잦은 약제처리를 요구한다. 본 연구에서는 동전마름병에 대한 농약의 단용 혹은 다른 약제와의 혼용 처리를 통해 약제의 효과를 평가하고, Rhizoctonia solani에 의한 브라운 패치(brown patch)와 Pythium aphanidermatum에 의한 피시움마름병에 대한 이차 방제효과(secondary effect)도 조사하였다. 평가기간동안 동전마름병은 유리한 기상조건으로 인하여 평가하기에 적당한 병 발생을 보였다. 처리한 살균제 중 Rhapsody 단용처리를 제외한 모든 살균제의 단용 혹은 혼용처리에서 동전마름병에 대한 유의성 있는 방제효과가 인정되었다. 또한 동일한 처리구에서 브라운 패치에 대한 병 방제효과도 인정되었다. 모든 살균제에서 약해는 관찰되지 않았다.