승마 속도변화에 따른 기승자세의 각운동학적 비교분석 : 30년 경력 KCC 기승자의 사례연구

현승현 ( Seung Hyun Hyun ),류재청 ( Che Cheong Ryew ),이애리 ( Ae Ri Lee ) 제주대학교 체육진흥센터(구 제주대학교 체육과학연구소) 2015 체육과학연구 Vol.21 No.-

골프 퍼팅 시 목표거리에 다른 퍼터헤드와 신체정열의 운동학적 비교분석

현승현(Hyun, Seung-Hyun),류재청(Ryew, Che-Cheong) 한국체육과학회 2013 한국체육과학회지 Vol.22 No.4

This purpose of this study was undertaken to analyze the pathway of the putter head & difference of body alignment according to target distances(3m, 15m) in golf putting motion. The variables analyzed were consisted of displacement(X, Y, Z axis) and velocity(X, Y, Z axis) of the putter head, and trunk inclination(FR angle, LR angle) during putting stroke. Six female players participated in the study were composed of general golfer(Less Skilled Golfer) and junior national team golfer(Elite Skilled Golfer’s). The general golfer’s(junior national team players) characteristics were mean 163.66±5.62cm(161.83±1.42cm)in height, mean 59.13±5.63kg(60.76±7.25kg)in body weight, mean 6.66±0.57(6.00±1.00)years in career and mean handy 66.33±1.15(66.33±1.15) hole-in score respectively. The results analyzed from the above were as follows; 1. The velocity of putter head showed higher in 15 meters than that of 3 meter during impact. 2. The putter head displacement in X-axis showed the shorter movement but verical displacement(Z axis) and Y-axis showed the longer movement according to increase of target distance. 3. FR angle in trunk showed the constant during putting motion according to players and target distances. Also LR angle in trunk showed the more constant lateral learning of trunk according to increase of target distance during impact & follow through phases.

여자골퍼의 어프로치 거리에 따른 퍼팅자세의 운동학적 비교분석

현승현(Hyun, Seung-Hyun),고명식(Ko, Myungl-Sikg),류재청(Ryew, Che-Cheon) 한국체육과학회 2012 한국체육과학회지 Vol.21 No.3

This study was to analyse the effective putting skills and get the data about kinematic variables needed for golfers by comparing the putting shots of each 3 meters and 15 meters, which both successful and failed putting shots to the pin in putting green respectively. The results of the above were as follows; he elapsed time of 15 meters putting showed longer than those of 3 meters on average. During golf putting motions, the left fright laterally of trunk position changes of 15 meters putting are larger than those of 3 meters putting on average during both downswing and follow-through phases. Vertical body displacements in 15 meters putting are also larger than those of 3 meters putting. The putter head speeds of 15 meters putting are faster than those of 3 meters during back-swing. And also during downswing and follow through phases, the speeds of 15 meters putting are faster than those of 3 meters. in the case of left elbow did not show significant difference statistically from address to impact phases. But left elbow was more flexed in 15 meters putting in follow through phases. And left shoulder are more extended in 15 meters putting than those of 3 meter putting. The changes of left and right hip joint angles are not different statistically between two putting motions. But in impact motions of 15 meters putting downswing phases, right joint was more spreaded. And left hip joint was more bended in 15 meters putting.

평지보행과 계단내리기 시 하지관절과 체간기울기 동작의 상관관계분석

현승현(Hyun, Seung-Hyun),류재청(Ryew, Che-Cheong) 한국체육과학회 2013 한국체육과학회지 Vol.22 No.6

The purpose of this study was to analyse the correlationship relative to variables of Lower extremities" Movement and Trunk Tilting angle in downward Stairs and Level Walking. To achieve the study goal, Total 12 young healthy women(Level walking: n=6, Downward stairs: n=6 respectively) participated in this study. The variables analyzed were consisted of angular displacement(hip, knee, ankle) and trunk inclination(FR angle) during downward stairs and level walking. The results analyzed from the above were as follows; 1. Downward stairs showed more extended posture in left?right hip joint than that of level walking during initial contact and also showed more flexed in left knee?ankle than that of level walking. 2. Downward stairs showed more flexed in right knee?ankle than that of level walking during mid-stance. 3. Downward stairs showed more flexed in left knee?ankle, right knee, ankle than that of level walking during toe off. 4. The correlation among extremities showed negative correlation(r=-.836) between right ankle(downward stairs) and right hip(level walking), also showed negative correlation(r=-.728) between left angle(downward stairs) and right knee(downward stairs), also showed negative correlation(r=-.750) between hip(downward stairs and left ankle(level walking) 5. The correlation between FR angle(downward stairs) and left knee(downward stairs) showed negative relationship(r=-.727), also relationship between FR angle(level walking) and right ankle(level walking) showed negative correlation(r=.-733) respectively.

계단내리기 시 우세,비우세 체지의 가방착용과 무게변화에 따른 지면반력 파라미터 분석

현승현 ( Seung Hyun Hyun ),이애리 ( Ae Ri Lee ),류재청 ( Che Cheong Ryew ) 한국운동역학회 2014 한국운동역학회지 Vol.24 No.1

The purpose of this study was to analyze of the GRF (ground reaction force) parameters according to the change of positions and weights of bag during downward stairs between dominant and non-dominant in upper & lower limbs. To perform this study, participants were selected 9 healthy women (age: 21.40±0.94 yrs, height: 166.50±2.68 cm, body mass: 57.00±3.61 kg, BMI: 20.53±1.03 kg/m2), divided into 2 carrying bag positions (dominant arm/R, non-dominant arm/L) and walked with 3 type of bag weights (0, 3, 5 kg) respectively. One force-plate was used to collect GRF (AMTI OR6-7) data at a sample rate of 1000 Hz. The variables analyzed were consisted of the medial-lateral GRF (Fx), anterior-posterior GRF (Fy), vertical GRF (Fz), impact loading rate and center of pressure (COPx, COPy, COP area, COPy posterior peak time) during downward stairs. 1) The Fx, Fy, Fz, COPx, and COP area of GRF were not statistically significant between dominant leg and non-dominant leg, but non-dominant leg, that is, showed the higher COPy, and showed higher impact loading rate than that dominant leg during downward stairs. 2) In bag wearing to non-dominant arm, Fx, Fz, COPx, COPy, impact loading rate and COP area showed increase tendency according to increase of bag weights. Also, against bag wearing to dominant arm, non-dominant showed different mechanism according to increase of bag weights. The Ground Reaction Force parameters showed different characteristics according to the positions and weights of bag during downward stairs between dominant and non-dominant arm.

승마 속보 시 미숙련자에게 적용한 하지장 비율 74.04% 등자길이 피팅의 기승자세 효과

현승현 ( Seung Hyun Hyun ),류재청 ( Che Cheong Ryew ) 한국운동역학회 2015 한국운동역학회지 Vol.25 No.3

Objective : The purposes of this study was to analyze the effects of the stirrup length fitted to the rider``s lower limb length and it’s impact on less skilled riders during trot in equestrian events. Methods : Participants selected as subjects consisted of less skilled riders(n=5, mean age: 40.02±10.75 yrs, mean heights: 169.77±2.08 cm, mean body weights: 67.65±7.76 kg, lower limb lengths: 97.26±2.35 cm, mean horse heights: 164.00±5.74 cm with 2 type of stirrups lengths(lower limb ratio 74.04%, and 79.18%) during trot. The variables analyzed consisted of the displacement for Y axis and Z axis(head, and center of mass[COM]) with asymmetric index, trunk front-rear angle(consistency index), lower limb joint(Right hip, knee, and ankle), and average vertical forces of horse rider during 1 stride in trot. The 4 camcorder(HDR-HC7/HDV 1080i, Spony Corp, Japan) was used to capture horse riding motion at a rate of 60 frames/sec. Raw data was collected from Kwon3D XP motion analysis package ver 4.0 program(Visol, Korea) during trot. Results : The movements and asymmetric index didn``t show significant difference at head and COM, Also, 74.04% stirrups lengths in trunk tilting angle showed significant difference with higher consistency than that of 79.18% stirrups lengths. Hip and knee joint angle showed significant difference with more extended posture than that of 74.04% stirrups lengths during trot. Ankle angle of 79.18% stirrups length showed more plantarflexion than that of 74.04% stirrups lengths. Average vertical force of rider showed significant difference with higher force at 79.18% stirrups lengths than that of 74.04% stirrups lengths during stance phase. Conclusion :When considering the above, 74.04% stirrups length could be effective in impulse reduction with consistent posture in rather less skilled horse riders.

계단 오르기와 내리기 시 가방착용 위치가 지면반력 파라미터에 미치는 영향

현승현 ( Seung Hyun Hyun ),류재청 ( Che Cheong Ryew ) 한국운동역학회 2015 한국운동역학회지 Vol.25 No.1

Purpose : The purpose of this study was to investigate the influence on the ground reaction force parameters according to wearing positions ofbackpack for during stair ascending and descending· Methods : Participants selected as subject were consisted of young female(n=10) and performed stairs walks(ascending and descending) with 2 types ofwearing position(front of trunk[FT], rear of trunk[RT])· Passive(Fz 1) and active(Fz 2) forces of the vertical GRF were determined from time functionand frequency domain· Also shear forces(Fx, Fy 1, Fy 2), dynamic postural stability index(MLSI, APSI, VSI, DPSI), loading rate and center of pressure(COPx, COPy, COP area) were calculated from time function and frequency domain· Results : Fx, Fy 1, Fy 2, and Fz 1 in GRF didn`t show significant differences statistically according to the wearing positions of backpack(p>·05), butstair descending showed higher forces than that of stair ascending· Particularly, Fz 2 of stair ascending showed higher forces than that of stairdescending(p<·001), RT types showed higher than that of FT types(p<·05)· MLSI, APSI, VSI, and DPSI of stair descending showed the increasedstability index than that of stair ascending(p<·05), MLSI of RT types showed the decreased stability index than that of FT types(p<·05)· Loading ratedidn`t show significant differences statistically according to the wearing positions of backpack(p>·05), but stair descending showed higher loading ratethan that of stair ascending(p<·001)· Also, COPx in stair descending showed the increased movement than that of stair ascending(p<·05)· Conclusions : A backpack of 10 kg(10 kg(ratio of body weights 17·61±1·17%) showed significantly change GRF parameters according to wearingpositions during stair ascending and descending· If possible, we suggest that the dynamic stability, in case of stairs walking with a smaller weights canbe further improved·

말의 4족 보법에서 속도변화에 따른 전족 움직임의 운동능력 분석

현승현 ( Seung Hyun Hyun ),류재청 ( Che Cheong Ryew ) 한국운동역학회 2015 한국운동역학회지 Vol.25 No.4

Objective : The purposes of this study was to analyze the locomotive movement of forelimbs according to changes in velocities in the quadruped cadence of horses. Methods : Horses selected as subjects consisted of Jeju pony horses (heights of withers: 1.23±0.51). Two camcorders (HDR-HC7/HDV 1080i, Sony Corp, Japan) were used to capture the movement of the horses’ forelimbs at a rate of 60 frames/sec. Additionally, raw data was collected from Kwon3D XP motion analysis package ver 4.0 program (Visol, Korea) with DARTFISH (DFKREA., Korea) video software solution. The variables analyzed consisted of 1 step lengths, 1 stride lengths, stance time, swing time, 1 stride time, velocity while walking, and trot of the horses. A two-way ANOVA and paired t-test of the variables by velocity and phase were treated at .05 level of significant difference, statistically. Results : The time elapsed of walk(stance: 0.63 sec[63.86%], swing: 0.35 sec[36.14%], 1 stride time: 0.99 sec respectively) showed significant difference with more delay than that of trot(stance: 0.29 sec[45.73%], swing: 0.34 sec[54.27% ], 1 stride time: 0.63 sec respectively), and also showed significant difference at trot in interaction (stance time>tort swing>walk swing>walk stance). The 1 step lengths and stride lengths in trot showed significant difference with longer than that of walk. Velocity of Trot showed significant difference statistically with higher than that of walk Conclusion : The horses’ velocity during 1 step lengths and 1 stride lengths showed a proportional relationship, but the correlation between the horses’ velocity and stance time showed a negative relationship during the quadruped cadence.

지방행정정보화가 전자주민참여에 미친 영향 분석 - 기초자치단체를 중심으로 -

현승현 ( Seung Hyun Hyun ),신유호 ( You Ho Shin ),이병기 ( Byeong Ki Lee ),김건위 ( Kun Wee Kim ) 한국지방행정연구원 2007 地方行政硏究 Vol.21 No.3

지역경제자본의 생산성 변화 및 결정요인 분석 -광역자치단체를 중심으로-

현승현 ( Seung Hyun Hyun ),김건위 ( Kun Wee Kim ),이병기 ( Byeong Ki Lee ) 한국지방행정연구원 2008 地方行政硏究 Vol.22 No.4