기합소리 유형에 따른 H-reflex 변화와 MVIC변화 분석

정익수 ( Ik Su Jeong ),오정환 ( Cheong Hwan Oh ),이동진 ( Dong Jin Lee ),이건희 ( Gun Hee Lee ),이진 ( Jin Lee ) 한국운동역학회 2009 한국운동역학회지 Vol.19 No.4

초등체육영재의 수직점프 수행 결과에 대한 운동역학적 분석

정익수(Ik Su Jeong),오정환(Cheong Hwan Oh),이동진(Dong Jin Lee) 한국체육교육학회 2012 한국체육교육학회지 Vol.17 No.2

체육영재에 선발된 D광역시 초등학교 저학년(2,3학년) 23명과, 고학년(4,5학년) 26명의 아동들을 대상으로 본 연구에서는 운동역학적인 변인으로 지면반력을 측정하고, 신체적 요인인 근력과 관련하여서는 무릎의 최대 각속도 및 신장, 좌고, 체중을 비교 분석하였으며, 운동학적인 변인으로는 무릎관절의 최소각을 변인으로 하여 수직점프를 수행한 결과 다음과 같은 결론을 얻었다. 첫째, 초등학교 저학년과 고학년의 두 집단 간에 신체적 특성은 모두 유의한 차이가 나타났다. 둘째, 수직점프수행과 관련하여 측정된 변인 간에는 수직점프 수행력에서만 두 집단 간 유의한 차이가 나타났다. 셋째, 수직점프 수행력과 신체적 특성과의 상관관계는 초등학교 고학년에서만 신장과 높은 상관을 보였다. 넷째, 수직점프 수행력과 최대 수직힘, 무릎관절의 최대각속도, 무릎관절의 최소각과의 상관관계는 초등학교 저학년 집단에서만 무릎관절의 최소각이 가장 높은 역상관 관계를, 무릎관절의 최대 각속도는 높은 상관관계를 보였으며, 고학년 집단에서는 세 변인 모두 수직점프 수행력과 낮은 상관관계를 보였다. With the subjects of 23 lower-grade elementary schoolers (2nd and 3rd grade) and 26 upper-grade elementary schoolers (4th & 5th grade) who are selected as athletically gifted children, the study measured kinetic variables with ground reaction force, conducted a comparative analysis on angular velocity of knees, heights, sitting heights and weights regarding strength, a physical factor, and reached the following conclusions after performing vertical jumping with the variables of the minimum angle of knee joints. First, physical characteristics of the both groups of elementary school low-graders and upper graders showed significant differences. Second, the two groups showed a significant difference only in vertical jumping performing abilities among the variables measured in relation to vertical jumping performance. Third, the correlation between vertical jump performance and physical characteristics is found to be high only in the upper grade elementary schoolers. Fourth, in terms of the correlation between vertical jumping performance and maximum vertical force, the maximum angular speed of knee joints and the minimum angle of knee joints, only minimum angle of knee joints showed the highest inverse correlations followed by the high correlation of maximum angular speed of knee joints while all the three variables showed low correlation with vertical jumping performance.

임상연구 : 두부 하강, 외회전 자세에서의 내경정맥과 경동맥의 관찰

정익수 ( Ik Soo Chung ),권민아 ( Min A Kwon ),황희윤 ( Hee Youn Hwang ),박정헌 ( Jeong Heon Park ),여진석 ( Jin Seok Yeo ),김정수 ( Chung Su Kim ),함태수 ( Tae Soo Hahm ),이상민 ( Sang Min Lee ),조현성 ( Hyun Sung Cho ) 대한마취과학회 2006 Korean Journal of Anesthesiology Vol.51 No.1

Background: This study evaluated the position and relationship between the right internal jugular vein (IJV) and the surrounding external landmarks using ultrasonography. Methods: Fifty-four patients undergoing central vein access for cardiac surgery were enrolled in this study. The IJV, carotid artery (CA) and sternocleidomastoid muscle (SCM) at the cricoid cartilage level in 15˚ trendelenburg position with 30˚ head rotation were examined using a two dimensional ultrasound transducer of a TEE machine. Images of the vessels and the demographic data of the patients were recorded and analysed. Results: At the level of the cricoid cartilage, the position of the right IJV was medial to middle of the clavicular head of the SCM muscle in 26 cases (48.2%), lateral in 11 cases (20.4%) and just above the middle of clavicular head of the SCM muscle in 17 cases (31.5%). In 43 patients (79.6%), the IJV overlapped the CA anterolaterlly < 5 mm, and these cases were regarded as normal. Ten patients (18.5%) had a medially positioned IJV overlapping the CA more than 5 mm and the IJV was positioned lateral to CA in 1 (2%) patient. The mean ratio of the overlapped diameter and the diameter of the CA was 33.6% and the overlapping ratios were greater than 50% in 10 patients (31.4%). The mean skin-to-vein distance at the angle of 30˚ was 1.82 cm. Conclusions: In 18.5% of patients positioned in the 15˚ Trendelenburg position, with their head turned to the left 30˚, the IJV overlapped the CA medially more than 5 mm, which increased the risk of a carotid puncture using the blind technique. (Korean J Anesthesiol 2006; 51: 11~6)

크라우칭 스타트시 반발력과 반응시간 측정을 위한 향상된 정밀센서 개발

이정태(Jeong Tae Lee),오정환(Cheong Hwan Oh),정익수(Ik Su Jeong) 한국사회체육학회 2011 한국사회체육학회지 Vol.0 No.46

This study intends to develop a more improved starting block precision sensor for enhancement of performance and motor mechanical analysis in short-distance track race. The production involved attaching strain gauge to the symmetric beam structure for the commercial starting block, which was found to show 5 times the improved effects, indicating that the beam structure devised in this study is effective, and it appears that credible measurement can be achieved. In the future, additional study will be conducted on the influence of training using starting block sensor on starting position correction and record improvements targeting the short-distance track athletes.

손가락 근력 측정장비 개발을 통한 남녀 근력 차이비교

이정태(Lee Jeong-Tae),정익수(Jeong Ik-Su) 한국코칭능력개발원 2012 코칭능력개발지 Vol.14 No.1

농구 3득점 점프슛 동작의 운동역학적 분석

이동진 ( Dong Jin Lee ),정익수 ( Ik Su Jeong ) 한국운동역학회 2010 한국운동역학회지 Vol.20 No.1

The purpose of the study was to analyze kinetic factors required to the three-point jump shot of the basketball games through 3-D analysis and ground reaction force(GRF) analysis. Six university male players participated in this study. The results of the study were showed that (1) resultant velocity in the center of mass(COM) was 0.84±0.27 m/s since a player didn`t shot a ball in the highest peak and shot ball at the moment of going up forward and vertical movement. Therefore, it is necessary to find a proper timing to shot a ball; (2) the angular velocity was largely increased in upper arm and fore arm out of the upper-limb segments and the hands had the largest angular velocity since the body is in a fixed situation and angular speed is rapidly increased by the wrist` snap with the rapid movement of upper arm and forearm at the time of release a ball; (3) it is judged that a player can shot a ball at the accurate and high release point when the player collects power vertically to the maximum by keeping GRF to the right and the rear in a proper way and by keeping the body`s balance so that a large power may not be dispersed.

한국 남자 포환던지기선수에 대한 운동학적 분석

오정환(Cheong Hwan Oh),신의수(Eui Su Shin),정익수(Ik Su Jeong),이진(Jin Lee) 한국사회체육학회 2012 한국사회체육학회지 Vol.0 No.49

This research aims to kinematically analyze the movements of Korean male shot-putters who participated in IAAF World Championships Daegu 2011. To accomplish this purpose, this research analyzed seven factors executive time of delivery phase, center of mass (COM) displacement, center of mass (COM) velocity, release angle, release height, release velocity and shot trajectories of ball. This research drew the following conclusions. First, for executive time of delivery phase, P2 (Phase 2) was long. So, horizontal rapid acceleration should be obtained by shortening the executive time of glide phase. This will exercise a positive influence on a throwing distance. Second, vertical displacement of center of mass is the process of momentum transfer from proximal muscle to distal muscle in shot-putting. During the process, in E3 (Event 3) energetic knee extension is done to transfer effective and explosive powers. A shot-putter should do the following sequential movements by using elasticity of waist twisting: moving the upper body forward and stretching one arm. Third, COM velocity according to executive time of delivery phase falls in the landing moment of back feet (i.e. E3 (Event 3)) and the release moment (i.e. E5 (Event 5)). A shot-putter needs an active play in that the passive play of the shot-putter who considers the foul of release moment acts as a factor of reducing COM velocity and that the reduction of speed interrupts momentum transfer. Fourth, contrary to world-class/international shot-putters, Korean players showed greater differences of release velocity compared to release angle and release height. To overcome this, they should increase COM velocity in E3 and E5 more. Active and dynamic movements are prerequisite for an increase in the speed. Finally, shot trajectories of ball showing its movements and re lease direction tend to fly to the right when a shot-putter releases the ball. The tendency is caused by the wrong rotation of the body, that is, the improper momentum transfer in the skill types for glide of release methods of straight line. This results in a loss of throwing distance. To make up for the weak point, a shot-putter should correct his body rotation. This can be expected to contribute to a rise in release velocity acting as an important factor of throwing distance.

2011 대구세계육상선수권대회 Gilde Type 포환던지기 한국선수와 결승 1, 3위 선수와의 운동학적 비교분석

오정환 ( Chow Hwan Oh ),최수남 ( Su Nam Choi ),신의수 ( Eui Su Shin ),이정태 ( Jeong Tae Lee ),정익수 ( Ik Su Jeong ),배재희 ( Jae Hee Bae ),박승범 ( Seung Bum Park ) 한국운동역학회 2011 한국운동역학회지 Vol.21 No.5

The purpose of this study was to analyze, in real time, the glide motion and release motion of domestic athletes and gold and bronze medalists employing the glide technique for the men`s shot put at the Daegu World Athletic Championship in 2011. In the glide motion, the Korean athletes had a relatively high body center and shot put heights and lager stretching angles for their hips and knees. In the delivery phase, which shifts to the release phase, the Korean athletes showed slower vertical body center and shot put speeds, and they changed the phase, to the release phase by using a small body angle. In the release phase, the Korean athletes showed differences in their projection speeds and vertical body center speeds. The world-famous players showed high angle speeds, which refer to the composition of the rotation force at the moment of release (body, hip, and shoulder line). In the release phase, the Korean athletes did not have fully stretched hip and knee angles, which might have negatively influenced the vertical speed, because the Korean athletes showed relatively low projection heights and projection angles, it was found that they need to enhance the muscular power of their, throwing arms and lower limbs.

2011 대구세계육상선수권대회 남자 포환던지기 결선경기의 운동학적 분석

오정환 ( Cheong Hwan Oh ),신의수 ( Eui Su Shin ),최수남 ( Su Nam Choi ),정익수 ( Ik Su Jeong ),배재희 ( Jae Hee Bae ),이정태 ( Jeong Tea Lee ),박승범 ( Seung Bum Park ) 한국운동역학회 2011 한국운동역학회지 Vol.21 No.5

This study had two purposes. The first was to analyze the period of the final record set by the male shot-putters in the IAAF World Championships, Daegu 2011 from the point of view of kinematics. The other was to identify an efficient movement for shot putting based on the analysis. The research used the eight finalists of in the championship as subjects. We analyzed the seven most important kinematic factors in shot putting based on the type of technique: the execution time of the delivery phase, release velocity, release angle, release, center of mass (COM) velocity, and shot trajectories, The analytical results showed the following average figures for the record 12 meters: execution time of the delivery phase: (0.19 s), release height: (2.06 m), release angle: (34.68°), release velocity: (13.25 m/s), angular velocity of shoulder: (922.38°/s), and angular velocity of pelvis: (479.50°/s). Further, the results showed that the highest COM velocity was 2.25 m/s and the shot trajectories were close to a straight line in the release phase.

VDT 작업시간에 따른 목의 가동범위와 근전도 분석

오정환(Oh, Cheong-Hwan),신의수(Shin, Eui-Su),정익수(Jeong, Ik-Su) 한국체육과학회 2016 한국체육과학회지 Vol.25 No.3

The purpose of this study was to investigate the range of motion and muscle activity in the neck when the work hours or two hours if there is any difference. In this study to achieve the purpose of the study it was chosen as 10 VDT workers. This study was used as a control object and a high-speed camera to analyze a 3D motion analysis program uses Kwon3D XP. And TeleMyo 2400T G2 was used for the analysis of muscle activity of sternocleidomastoid, cervical paraspinals, and upper trapezius. Statistical analysis was carried out for repeated measures ANOVA for comparative analysis of the the Pre, an hour and two hours work, post verification was contrast verification. and statistical analysis using the SPSS 21.0 program. First, the range of movement of the neck of the VDT working hours showed a significant difference flexion, extension, rotation left and right. And shown to the neck two hours is more rigid than an hour. Also been shown to a high rate of decrease of the rotational range of motion than the flexion and extension. Second, sternocleidomastoid and upper trapezius muscle activity in accordance with VDT working time showed significant differences in both the left and right. And muscle activity of the cervical paraspinals showed a significant difference in left. an hour working time than two hours working time is shown to reduce the muscle activity of the sternocleidomastoid, upper trapezius, and cervical paraspinals. And decrease rate of muscle activity is on the left upper trapezius and cervical paraspinals higher than elsewhere. Neck rigid was greater than B is to A, the rotation was smaller than the range of motion flexion and extension. sternocleidomastoid, upper trapezius, and cervical paraspinals muscle activity was found to be too low.