• 전기학회논문지
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• 제58권6호
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• pp.1071-1077
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• 2009

Because several winds cause the a fault of transmission supply, KEPCO trys to protect the the trouble and supply the power stably. Kepco find out the weak mountains by winds and strengthen the power equipment annually. Power quality is the competition power in the international world and satisfy the customer using th power Therefore this paper deals with the fault relation between winds and transmission line.

• 한국운동역학회지
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• 제23권4호
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• pp.387-393
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• 2013

The purpose of this study was to investigate the difference of kinematic factors acting in the body during a normal swing and a swing taken with an intention to increase driving distance by female pro golfers. Female pro golfers may increase driver clubhead speed and improve driving distance through maintaining a large X-factor angle during backswing and delaying the uncocking period by rapidly shifting the weight to the left foot during downswing.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 D
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• pp.2411-2413
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• 2003

A new small humanoid robot system is developed in this paper. The humanoid robot has total 20 DOFs : 6 DOFs in each legs, 3 DOFs in each arms, and 2 DOFs in head, 34cms in height, and 2kgs in weight. The robot has the following characteristics: (1) PDA as host controller (2) network-based joint controller (3) wireless camera attached in robot's head (4) mechanism design by CATIA and high speed laser prototyping (5) graphic MMI(Man-Machine Interface) utilizing the CATIA data. By using ADXL inclination sensor, we implement the rope swing with the robot leg motion as well as walking.

• 한국운동역학회지
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• 제30권1호
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• pp.27-35
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• 2020

Objective: The purpose of this study was to investigate the influence of clubhead velocity through regression analysis on the magnitude and time difference of the forward-backward, mediolateral, and vertical ground reaction peak forces generated by force plate during golf swing. Method: 16 subjects (age: 20.5±4.2 yrs, height: 176.0±5.4 cm, weight: 77.8±5.9 kg, handy: 2.4±1.7) who is elite golf player in high school and university, participated in this study. The study method adopted three-dimensional analysis with 8 cameras and ground reaction force measurement with two force plate. The analysis variables were clubhead velocity, and ground reaction analysis variables set four events in each graph based on the peak forces commonly generated in Fx, Fy, and Fz graphs of the ground reaction data during the golf swing. Results: As a result of analyzing the influence of ground reaction magnitude difference on clubhead velocity, the influence on clubhead velocity was ym4, zm1, xm4, zm2. The larger ym4, xm4, zm1, the fasterthe clubhead velocity, but the smallerthe zm2, the faster the clubhead velocity. And in time difference, the influence on the clubhead velocity was in the order of xt4, zt1, zt3. The shorter xt4, zt1, zt3 showed faster clubhead velocity. Conclusion: The leftfoot played a leading role in increasing the velocity of the clubhead. Although the result was caused by the interaction of the right foot and the left foot during the swing, the role of the left foot is relatively large.

• 한국의류산업학회지
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• 제23권1호
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• pp.98-105
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• 2021

This study investigates and analyzes user preferences for golf wear with a sense of wear and smart function for the development of smart golf wear based on user convenience. A survey was conducted on 124 males in the age range of 40-60s that consisted of professional golfers, amateur golfers and the public with golf experience (such as major golf consumers) from August 1 to August 30, 2019 (IRB NO. 1040198-190617-HR-057-03); consequently, a 117 copies were accepted for analysis. The findings are as follows. The elbow (4.3%) of golf wear is unsatisfactory. The important part of the golf swing motion is the shoulder (39.3)>, elbow (30.8%)>, and wrist (6.8%). In addition, the unsatisfactory wearing of golf wear due to golf swing movements indicated that the shoulder or elbow area was pulled or the bottom of the top was raised during the back swing movements. The survey results on the expected discomfort when wearing smart wear are 'discomfort of obstruction when wearing' (53.8%), 'discomfort of washing' (17.1%), and 'weight of attached machine' (13.7%). Opinions such as 'Will not feel good when the sensor is attached' were investigated. The examination of the preference for golf wear equipped with smart functions indicated that a posture correction function to correct the golf swing posture is the most desired quality that is also considered important when correcting posture.

• 국제물리치료학회지
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• 제2권2호
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• pp.294-300
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• 2011

The purpose of this study was to investigate the influence of the static pelvic inclination and declination in the static standing position on weight bearing rate and gait elements. Fourteen healthy adults in their twenties were participated. Two groups of healthy adults were allocated in this study: above and below the average of pelvic tilt. The correlation between the pelvic inclination, weight bearing rate and gait elements were measured. There was a statistical correlation between the pelvic tilt and step. Also, there was a statistical difference when we compared anterior declination with swing period and posterior declination with step. There was an asymmetric correlation between pelvic tilt and step. However, there was no statistical difference between the groups above and below the average of pelvic tilt. This result indicates that dipper pelvic inclination doesn't affect the asymmetry of step.

• 한국운동역학회지
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• 제17권2호
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• pp.31-40
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• 2007

Proper weight shifting is essential for a successful shot in golf swing and this could be described by means of the ground forces between the feet and ground. It is assumed that the ground forces would different according to the club used because the length and swing weight of each club is different. But, in present, it is not clear what changes are made by the change of clubs and this affect the swing motion. Therefore this study focused on the investigation of the changes of the ground forces and ground reaction forces (GRF) by the change of club length. The subjects were three professional male golfers. Four swings (driver, iron 3, iron 5, and iron 7) for each subject were taken by two high speed video cameras and two AMTI force platforms were used to measure the GRF simultaneously. Kwon GRF 2.0 and Mathcad 13 software were used to post processing the data. Changes of the three major component of GRF (Vertical, lateral, anterior-posterior force) at 10 predefined events were analyzed including the maximum. Major findings of this study were as follows. 1. Vertical forces; - There were no significant changes until the top of backswing. - Maximum was occurred at the club horizontal position in the downswing for both feet. The shorter club produced more maximum forces than longer ones in the left foot, but reverse were true for the right foot. - Maximum forces at impact shows the same patterns. 2. Lateral forces; Maximum was occurred at the club horizontal position for both feet, but there were no lateral forces because the direction of two forces was different. Maximum force pattern by different clubs was same as the vertical component. 3. Anterior-posterior forces; - This component made a counter-clock wise moment about a vertical axis located between two foot until the club vertical position was reached during the backswing, and reverse moment were produced when the club reached horizontal at the downswing. - Also this component made a forward moment about a horizontal axis located in the CG during the fore half of the downswing, and a reverse moment until the club reached vertical at the follow through phase. Maximum was occurred at the club vertical in the downswing for both feet. The longer club produced more maximum forces than shorter ones for both feet.

• 대한전기학회논문지:시스템및제어부문D
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• 제49권5호
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• pp.257-263
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• 2000

One of the basic assumptions in the static gait design for a walking robot is that the weight of leg should be negligible compared to that of body, so that the total gravity center is not affected by swing of a leg. Based on the ideal assumption of zero leg-weight, conventional static gait has been simply designed for the gravity center of body to be inside the support polygon, consisting of each support leg's tip position. In case that the weight of leg is relatively heavy, however, while the gravity center of body is kept inside the support polygon, the total gravity center of walking robot can be out of the polygon due to weight of a swinging leg, which causes instability in walking. Thus, it is necessary in the static gait design of a real robot a compensation scheme for the fluctuation in the gravity center. In this paper, a body impedance control is proposed to obtain the total gravity center based on foot forces measured from load cells of a real walking robot and to adjust its position to track the pre-designed trajectory of the corresponding ideal robot's body center. Therefore, the walking stability is secured even in case that the weight of leg has serious influence on the total gravity center of robot.

• The Journal of Korean Physical Therapy
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• 제26권1호
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• pp.1-8
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• 2014

Purpose: The aim of the present study was to understand the relationship between gait symmetry and functional balance, walking performance in stroke patients and to makes recommendation regarding the most suitable measure for standardization of expression of spatiotemporal gait symmetry. Methods: 45 subjects with stroke (31 men, 14 women, $57.3{\pm}10.3$ years old) participated in this study. Gait symmetry was calculated by equations of symmetry ratio (SR) and symmetry criterion (SC) for stance time, swing time, single leg support time (SLST), step length, and stride length. Spatiotemporal parameters were measured respectively by walkway system ($GAITRite^{TM}$ system). Limit of stability (LOS) by using forceplate (Balance Performance Monitor) during voluntary weight displacement and Berg Balance Scale (BBS) were measured as functional balance and Timed Up and Go test (TUG) and Functional Ambulation Category (FAC) were assessed as functional walking. Results: SR in stance time and swing time was correlation with BBS, TUG and FAC (p<0.05). SR in SLST only with BBS (p<0.01), SR in step length only with FAC (p<0.05). SC in stance time was correlation with BBS and TUG (p<0.05). SC in swing time and SLST with BBS, TUG and FAC (p<0.01), SC in step length with TUG and FAC (p<0.01), SC in stride length with BBS and FAC (p<0.01). Conclusion: Gait symmetry in spatiotemporal gait parameters provides meaningful information about functional balance and walking performance in stroke subjects. Our analysis may support the recommendations of the symmetry criterion as equation for standardization of gait symmetry.

• 한국운동역학회지
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• 제25권1호
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• pp.21-28
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• 2015

Objectives : The purpose of this study was to compare differences in muscle activities according to distance changes, and success or failure in relation to approaches during a round of golf in order to obtain basic data on golf swings. Methods : To achieve our research goal, we asked eight professional golfers playing for the Korea Professional Golfers' Association (height: $1.76{\pm}0.05m$, weight: $73.87{\pm}9.21kg$, career duration: $12.87{\pm}4.48yr$) to perform approach swings at distances of 30, 50, and 70 m. Results : No differences were observed in the muscle activity of the extensor carpi radialis that were caused by the distance changes. In addition, we found that the wrist extensors seemed unaffected by the increase in approach distance. Also, we found that the powers of the approach shots were driven by efficient movements rather than by the strength of the arms. We confirmed that when the distance of the approach increased, the golfers should perform their back-swing tops and follow-through right from the right to the left pelvic limb. To achieve successful approach swings despite distance changes, golfers should first work on the activity of the erector spinae to prepare for rotatory power in the P1 section. Moreover, golfers should increase the activity of the erector spinae on the left when they need to deal with the distance improvements in the P2 and P3 sections. Conclusion : In the light of the discussion above, we may infer that despite approach distance changes during a round of golf, ideal swings can be realized by consistent activities of the wrist extensor muscles and improved performances of the pelvic limb muscles. Furthermore, this study suggests that golfers should improve the consistency of muscle activities in all the other body parts to achieve the ideal swing.