• Journal of Korean Society of Steel Construction
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• v.14 no.3
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• pp.423-432
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• 2002

This study presented analytical and numerical solutions for spatial free vibration of nonsymmetric thin-walled circular curved beams. The closed-form solutions were obtained for in-plane free vibration analylsis of monosymmetric curved beams. Likewise, two types of thin-walled curved beam elements were developed using the third and the fifth order Hermitian polynomials. In order to illustrate the accuracy and usefulness of the present method, this study presented analytical and numerical solution and compared these with the results using the ABAQUS's shell elements. In particular, effects of the thickness-curvature as well as the inextensional condition were investigated on the free vibration of curved beams with nonsymmetric sections.

• Journal of The Korean Society of Integrative Medicine
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• v.7 no.4
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• pp.273-282
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• 2019

Purpose : The purpose of this study was to provide the effective method for exercise therapy in soccer player. Methods : 30 soccer players were recruited for subjects. The subjects were divided to dynamic stretching exercise combined tDCS (Group I), dynamic stretching exercise combined Sham-tDCS (Group II) of which 15 subjects were randomly allocated. The subjects were given 3 hour of soccer skill and performance and additionally given 20 minutes of dynamic stretching exercise combined tDCS and sham-tDCS for each group, five times a week, for 6 weeks. Their muscle activity and jump performance were analyzed before the intervention. After 6 weeks of the intervention, the mentioned parameters were measured once more for between-group analysis. Results : Comparative analysis of the muscle activity and jump performance between the groups I and groups II showed statistically significant difference. Conclusion : Such results revealed that dynamic stretching exercise combined with tDCS is effective in muscle activity and jump performance. Based on the current study, more effective program is to be proposed for neurologic and musculoskelectal disorder as well as soccer player. Based on the current study, studies that incorporates various combine of variable is required for development of effective tDCS program.

• Physical Therapy Korea
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• v.9 no.4
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• pp.45-52
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• 2002

이 연구의 목적은 수직착지시 성에 따른 슬관절 가동범위의 차이를 알아보는 것이다. 연구 대상자는 20대의 건강한 성인 48명(남자 25명, 여자 23명)이었다. 연구 대상자에게 40 cm 높이에서 한발로 뛰어내리도록 하고, 2차원 동작측정 기구인 CMS-HS를 이용하여 수직착지시 슬관절의 굴곡각도, 최대 슬관절 굴곡각도, 슬관절의 가동 범위, 각속도를 측정한 후, 남 여 두 집단간의 차이를 알아보았다. 이때 사용한 분석방법은 독립적인 두 표본 t-검정이었으며 축차적(stepwise) 다변량회귀분석을 이용하여 체중과 신장을 조절한 상태에서 남여 간에 차이가 있는지를 분석하였다. 그 결과 수직착지시 슬관절의 굴곡각도에서는 유의한 차이를 보이지 않았으나, 최대 슬관절 굴곡각도, 슬관절의 가동 범위, 각속도에는 유의한 차이가 있었다(p<.05). 체중과 신장이 조절된 조건 하에서 여자는 수직착지시 최대 슬관절의 굴곡각도와 슬관절의 가동범위가 남자보다 작았다. 이러한 결과를 통하여 수직착지시 여자가 남자보다 슬관절 손상의 빈도가 높은 이유 중의 하나는 여자가 슬관절을 덜 굴곡시킴으로 인해 바닥의 충격을 더 많이 받기 때문이라는 가능성을 발견하였다.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.15 no.2
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• pp.1-7
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• 2009

Purpose : to investigate change of isokinetic muscle strength and isokinetic muscle endurance of quadriceps femoris and hamstring after application of taping and static stretching. Methods : For this study, 14 male members of college soccer team participated in this research. Participants were divided into two groups: seven was assigned to a taping group(n=7) and the others were assigned to a static stretching exercise group(n=7). Main outcome was measured by using biodex. The isokinetic muscle strength test was processed at the speed of the $60^{\circ}$/sec five times, and isokinetic muscle endurance was processed at the speed of $180^{\circ}$/sec ten times. Results : From the outcomes of the measurement, the results show that there is a more significant difference in the taping group than in a static stretching exercise group. Conclusion : These results will be utilized for the preliminaries in the future.

• Journal of the Korean Society of Physical Medicine
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• v.18 no.4
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• pp.77-87
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• 2023

PURPOSE: The purpose of this study was to investigate the changes in the flexibility and elasticity of the muscles when the hamstrings were stretched in one direction and when they were stretched in three directions. METHODS: In this study the subjects were divided into two groups, namely the 'one-direction stretching exercise of the hamstring muscle in the neutral position' group (female: 14 people, male: 14 people) and the 'three-way stretching exercise' group (female: 12 people, male: 14 people) considering the positions of the three hamstring muscles. The elasticity and flexibility of the hamstring muscles were measured before and after the self-extension exercise, and the average value of two measurements was noted. To evaluate the flexibility of the hamstring muscle, a 'sit and reach' test was performed, and muscle elasticity was measured using the MyotonPRO® device. RESULTS: After the stretching exercise, flexibility increased in both groups. In terms of muscle elasticity, the body dynamic strength and resonance frequency of the stretching one-direction stretching group decreased after the stretching exercise. CONCLUSION: To alter the muscle characteristics and increase the flexibility when performing a stretching exercise, selecting and stretching only one muscle with the lowest range of motion yields effective results. The ideal technique to be employed appears to be to stretch the entire hamstring muscle in one direction from the neutral position.

• Journal of radiological science and technology
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• v.29 no.3
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• pp.177-184
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• 2006

Purpose: To evaluate the correlation between BMD and life habit such as drinking. exercise smoking or physical condition such as age, sex, height, weight, body mass index(BMI). Materials and Methods: I evaluated the BMD of the femoral neck and L2-L4 spines of 321 persons who took a regular health screening in Woosuk university oriental medical hospital from February to April in 2006 by dual energy bone mineral densitometry. Results: The age of persons ranged from 20 years to 75 years(mean $45.10{\pm}11.54$) and there were 160 males and 161 females. In males, BMD of the femoral head was highest at 2nd decade, BMD of the spine was highest at 4th decade, and BMD of both femoral head and lumbar spine was lowest at 6th decade. In fenales, BMD of both femoral head and lumbar spine was highest at 4th decade and lowest at 6th decade. Among the various physical conditions, only height of persons showed significant correlation with BMD in both males and females. BMD was increased according to increasing height. In males, BMD of persons who had habit such as drinking, exercise or smoking did not show significant change statistically. But in females, drinking group showed high BMD relative to non-drinking group in both femoral head and lumbar spine. Conclusion: BMD was different according to age, sex, height and life habit. Especially aged people showed osteoporotic change progressively. More persistent effort is needed to find out the factors decreasing BMD for prevention of problems by osteoporosis.

• Journal of the Korean earth science society
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• v.25 no.8
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• pp.663-673
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• 2004

This study has developed an interactive WBI to enhance learning effects on 'the Moon motion' for middle-school students. The quality of this examined by applying it to 20 science teachers and 49 middle school students 49. As a result, over 85% of the test subjects gave an affirmative response in the interest induction, the curiosity solving, and the degree of learning participation category, the degree of difficulty item. Response of the students with negative perception on science have changed positively(p<.05) after this WBI learning. In addition, we compared the learners' of knowledge prior and subsequent to 'the Moon motion'. As a result, it was found that the case of 'no concept' was enhanced more than the case having 'partly or ambiguously concept' for 'the Moon motion'.

• Journal of Sensor Science and Technology
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• v.10 no.1
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• pp.52-61
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• 2001

We propose a new saccadic eye movement system with visual selective attention. Saliency map models generate the scan pathways in a natural scene, of which the output makes an attended location. Saccadic eye movement model is used for producing the target trajectories to move the attended locations very rapidly. To categorize human saccadic eye movement, saccadic eye movement model was divided into three parts, each of which was then individually modeled using different neural networks to reflect a principal functionality of brain structures related with the saccadic eye movement in our brain. Based on the proposed saliency map models and the saccadic eye movement model, an active vision system using a CCD type camera and BLDC motor was developed and demonstrated with experimental results.

• Korean Journal of Applied Biomechanics
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• v.18 no.3
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• pp.93-105
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• 2008

This study was for the analysis of Kinematic variables, using 3 types of starting block position setting(25cm, 40cm, 35cm). The subjects of the study were 8 short-distance male runners. In the study, the most desirable block setting type for the runner who were average 180cm tall to get the good record was 45cm (distance between the starting line and the front block) and 40cm (distance between the blocks). In conclusion, the most favorable start in 100m race was to get the strongest propelling power at the start line. The most important technical point was quick responding ability to the start signal and reaching the maximum speed at the shortest time through the strong kick using the front leaning body angle and gravity. Type B start method has shown the most effective results for the improvement of the records in the 100m race.

• Journal of the Korean Applied Science and Technology
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• v.39 no.2
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• pp.335-339
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• 2022

The purpose of this research was to investigate the comparison of core muscle activities according to different performance in static Plank exercise. Ten "J" University's males(age, 23.20±0.65 years; height, 174.54±1.51 cm; body mass, 70.00±2.24 kg; and BMI, 22.94±0.51 kg/m²) completed this study as the subjects. Four type's static Plank motions were performed(full Plank, FP; elbow Plank, EP; side Plank, SP; reverse Plank, RP). For the EMG analysis, we measured the core muscle activities of right side on the rectus abdominis(RA), external oblique(EO), latissimus dorsi(LD), and erector spinae(ES). This research's results were as follows. LD and ES muscle activities were greatest during RP(p<.001). RA and EO muscle activities were greatest during EP(p<.001). Therefore, this results are anticipated to serve as basic data for static Plank performance applications in effective exercise programs.