• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.2028-2031
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• 2005

This paper concerns stress distribution of the soft golf clubs using FEM. The identification of the stress distribution of the soft golf clubs used the finite element method using ABAQUS. The soft golf clubs which were designated is a new golf clubs to keep a good health for the elderly. To design the soft golf clubs, we concerns two main purpose ; First, our efforts concentrate to reduce the weight of the soft golf clubs. We considers the change of material and geometry of the golf club‘s head and shaft. Second, it is to increase the size and shape of 'sweet spot' of the soft golf club’s head face. To accomplish this purpose, we made the various type of the soft golf club's head. In this paper, we simulates putter models of the soft golf clubs. The pre-processing which generates the mesh of the model used HyperMesh with geometry data by CATIA ver 5.0 This paper compares the stress distribution of putter type which was loaded.

• 한국운동역학회지
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• 제15권2호
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• pp.103-111
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• 2005

The purpose of this study was to analysis golf swing in accordance with each club using ground reaction force data. The subject of this study was current professional golf players in Korea. Golf clubs used for this study were driver, iron4, iron7, and pitching. The ground reaction force for left and right foot was collected by one Kistler and one Bertec force platforms. Also collected visual data by NC high speed camera to check the phase which was composed of address, top of backswing, impact and finish. Sampling rate was 600Hz both ground reaction forces data and visual data. The conclusion are as follows. 1. An aspect of change for ground reaction force was that the weight between the left foot and right foot were contrary to each other in general as the phase. 2. Without regard to the type of golf club, the ratio of necessary ground reaction forces for each phase in accordance with address, top of backswing, impact, and finish was comparatively identical. 3. According to the type of golf club, the tendency of Fy was not varied. In terms of Driver, at the moment of impact, the weight of foot-both right and left-was moved to the movement direction of golf because of the rotation force from swing.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2011년도 춘계학술대회
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• pp.157-158
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• 2011

골프채로 공을 치면 골프공은 충돌로 인하여 커다란 속도로 긴 거리를 날아간다. 본 논문에서는 골프채와 골프공이 충돌 한 후의 운동량의 크기를 구하고자 한다. 또한 골프채와 골프공의 충돌 시간과 공에 작용한 평균력을 구한다. 우리는 물체에 작용하는 충격량은 물체의 운동량의 변화화 같음을 알 수 있다. 그리고 평균력은 시간에의해 변하는 힘 대신에 어떤 물체의 실제 힘과 똑같은 충격량을 주는 일정한 힘임을 알 수 있다.

• 아시안잔디학회지
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• 제12권3호
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• pp.225-236
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• 1998

골프장 잔디를 가해하는 토양중의 굼벵이류 종류와 밀도등을 알아보기 위하여 7개도 2개 광역시 15개 골프장을 대상으로 조사한 결과 12종의 굼벵이류가 채집되었는데, 등얼룩풍뎅이(Anomala orientalis) 등 8속 11종은 동정이 되었고, 1종은 동정이 되지 않았다. 골프장에 따라서는 다양한 종구성을 보여 주었는데 등얼룩풍뎅이 유충의 피해가 가장 심하였다. 6곳의 골프장에서 주둥무늬차색풍뎅이(Adoretus tenuimaculatus)가 채집되어 일반적으로 널리 분포하고 있던 종이었으며, 밤색우단풍뎅이(Maladera castanea)는 5곳의 골프장에서 등얼룩풍뎅이, 검정풍뎅이(Holotrichia kiotoensis), 애우단풍뎅이(M. orientalis) 등도 4곳의 골프장에서 채집되었다. 한편, 3개 지역 골프장의 tee, fairway, green별 굼벵이류 종류와 밀도, 분포 깊이등을 월동기와 비월동기에 조사하였던 바, 월동기에는 등얼룩풍뎅이가 비월동기에는 주둥무늬차색풍뎅이가 우점종이었으며 굼벵이 밀도는 green이 tee나 fairway보다 낮았다. 분포 깊이는 동래골프장과 대구골프장에서는 계절별로 차이가 있었으나 진해 용원골프장에서는 차이가 없었다. 잔디종에 따른 가해 굼벵이의 종류는 차이가 없었다. 그러나 대엽고려지(Zoysia matrella)에서는 주둥무늬차색풍뎅이의 밀도가 높았고, 켄터키블루그라스(Poa pratensis)에서는 등얼룩풍뎅이의 밀도가 높았다. 그리고 골프장의 년수가 오래될수록 등얼록풍뎅이 유충의 밀도가 높았지만 분포하는 굼벵이류의 종류에는 차이가 없었다.

• 한국응용과학기술학회지
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• 제36권2호
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• pp.479-487
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• 2019

The purpose of this study is to present a caddie education program that can improve the performance of golf caddies in China by comparing and analyzing the golf caddie education programs in South Korea and China. Caddie education programs were collected from 4 golf clubs, 3 professional caddie education institutions and 8 public institutions in South Korea and 6 golf clubs and 2 professional caddie education institutions in China. The following results were obtained. Although the caddie training in China is conducted over more time and term than in South Korea, it is necessary to have an education program considering golf expertise and quality of customer service. Therefore, the caddie education program in China is composed of golf related education(golf etiquette, golf practice skill), caddie duty training(safety management, customer service and image making), and training for caddie(fitness management, injury prevention, skin care, and cost-saving etc.). In the future, the Chinese golf club industry will has a potential to develop. In order to provide a consistent and systematic education, manual training on caddie education and training on caddie master to manage caddies should be conducted.

• 대한의용생체공학회:의공학회지
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• 제31권2호
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• pp.141-150
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• 2010

The purpose of this study was to analyze the golf swing motion for a soft golf clubs and regular golf club. Soft golf is a newly developed recreational sports for all ages, including the elderly and the beginners of golf. To quantify the effect of using soft golf club, which much lighter club than regular clubs, a motion analysis has been performed using a 3D optoelectric motion tracking system that utilizes active infrared LEDs and near-infrared sensors. The subject performed swing motion using a regular golf club and a soft golf club in turn. The obtained motion capture data was used to build a 3D computer simulation model to obtain left wrist, elbow shoulder and lumbar joint force and torque using inverse and forward dynamics calculations. The joint force and torque during soft golf swing were lower than regular golf swing. The analysis gave better understanding of the effectiveness of the soft golf club.

• 한국운동역학회지
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• 제22권1호
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• pp.75-82
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• 2012

The purpose of this study was to suggest the proper shaft and head fitting methods of the golf club to increase the flight distance of the golf ball. Rotations per minute of the golf ball(RPM), ratio of Ball speed to club head speed(T-Ratio) and launch angle right after impact(LA), which are directly related to ball flight distance, were measured using Spectra with shutter speed of 1/1000sec at the constant head speed of 95mph which was controlled by robot golf swing machine. In order to investigate the effect of club shaft to the 3 selected variables, 10 shafts were used to make ten test clubs with one controlled club head which is the most commonly used by golf players. To measure the effect of the club head to the 3 selected variables, 6 golf club heads which are most commonly used by golfers were selected to make 6 test clubs with a controlled shaft which is one of the best known by players. The shafts and the heads were identified by statistical analysis to increase or decrease the RPM, T-ratio and LA. A proper fitting method of the selected shafts and the club head was suggested to increase the ball flight distance in golf.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.643-644
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• 2006

The purpose of this study is to experimentally analyze swing motion with soft golf clubs and compare with that with normal golf clubs. Soft golf is newly devised recreational sport based on golf but focus on the playability for the elderly. The subject fur the experiment performed swing motion using a normal golf club and a soft golf club in turn. The swing motion of the subjects was tracked using an opto-electric three-dimensional motion analysis system. The results were compared against those obtained with a normal golf club. The range of motion was analyzed along with top head speed for two cases. It was found that higher club head speed could be achieved with reduced range of motion at lumbar joint using soft golf club when compared against the swing using regular club. The lower range of motion fur lumbar bending means reduced risk of injury at the joint. So, it is projected that we can reduce the risk of injury with soft golf while maintaining the club head speed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.2011-2014
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• 2005

The purpose of this study is to compare the modal parameters of a newly developed soft golf club prototype, which is designed to be lighter than regular golf clubs, with those of a regular commercial golf club. The modal tests were performed with two kinds of boundary conditions. The first condition was free-free condition and the second was fixed-free condition. An impact hammer and a Fast Fourier Transform analyzer were used to obtain modal data. From the results, it was found out that the modal characteristics of the soft golf club prototype were close to those of the regular golf club although the weight of the soft club was lighter. Therefore, the soft golf club is expected to be able to convey similar feel to the golfers even with lighter weight. This would enable elderly golfers to swing easily with the soft golf club with same skill which they acquired with regular golf clubs but with reduced load to their muscles.

• The Korean Journal of Ecology
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• 제17권2호
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• pp.143-148
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• 1994

The relationships between microbial activity and physico-KDICical characteristics of soils were investigated in three golf courses of Kwanak, Gold and Korea Country Clubs, with different open years. The soil samples were collected in tee, fairway and rough. There were ranges of 4.80-5.55 in pH, $25.55-98.50{\mu}S$ / cm in conductivity, 10.96-16.73% in moisture content, 0.18-0.36g / g in water holding capacity, 3.68-5.39% in organic matter, and 0.10-0.25% in total nitrogen. Dehydrogenase activity(DHA) as an index of soil microbial activity was determined. DHA values of soil were $69.83-314.43{\mu}$g / g in three courses and showed the order of Kwanak>Gold>Korea Country Club with open year. This indicates that DHA was affected by several fertilizer treatments rather than herbicide and pesticide treatments. DHA was significantly different with golf clubs as well as golf courses and positively correlated with water holding capacity and total nitrogen.