• Journal of the Korean Applied Science and Technology
• /
• v.37 no.1
• /
• pp.114-123
• /
• 2020

The present study aimed the effects of power resistance training(PRT) on fitness, muscle mass and short physical performance battery(SPPB) elderly women. Thirty older woman(aged 70 over years) were divided in two groups : PRT(n=15) and traditional resistance training(TRT)(n=15). The volunteers trained three times a week, during 12weeks. Both groups performed an equal work output with load red color thera-band. Three sets of twelve repetitions of each exercise were performed with rest intervals of 60s between sets. According to the results. Main fitness were significantly difference in grip strength(TRT) and cardiopulmonary. Muscle was not significantly difference. And Timed up and go and 400m walking(TRT) were significantly difference. There is sufficient effects on between training method in fitness, SPPB but PRT training may yield better results compared with TRT.

• Journal of the Korean Applied Science and Technology
• /
• v.36 no.4
• /
• pp.1349-1357
• /
• 2019

The purpose of this study was to investigate to effect of core exercise with swiss ball on sarcopenia index in agriculture older women. A total of 30 subjects(15 Ex group, 15 Con group, 65 over agriculture older woman) were participated in this study. Intervention group were assigned to performing a progressive core exercise training program for 12 weeks(2 time/week). Dependent variable were grip strength, chair stand, muscle mass, 4m gait speed, Timed up and go, and 400m walking. As a result were following. Grip strength was not significantly difference but chair stand was significantly difference in time. And muscle mass was significantly difference in groups. And 4m gait speed, Timed up and go and 400m walking were significantly difference in time. In conclusion, lower body muscle strength and short physical performance battery by muscle activating with core muscle strength training.

• The Journal of the Korea Contents Association
• /
• v.10 no.3
• /
• pp.373-380
• /
• 2010

The purpose of this study was to evaluate the effects of recreational exercise on cognition, depression, dynamic balance and leg strength in elderly women. This study was nonequivalent control group pre-post test design. Subjects were divided into two group(exercise group=14, control group=13). Experimental group conducted recreational exercise program for eight-week. Cognition was assessed by K-WAIS(object assembly & digit symbol) and depression were assessed by questionnaire. Dynamic balance(DB) and leg strength(LS) were assessed by 244cm up & go and sit to stand respectively. The collected data analyzed by Wilcoxon singed rank test and Mann-Whitney U test. The exercise group significantly improved cognition(object assembly) and DB, but control group significantly reduced DB. DB in exercise group were significantly greater than in control group after eight-week. The program was effective on cognition and dynamic balance in elderly women.

• Proceedings of the KIEE Conference
• /
• 1998.07b
• /
• pp.546-548
• /
• 1998

초음파는 초음파 가공기나 초음파 세척기 등에 많이 이용되고 최근 액추에트로서 초음파 전동기가 주목을 받고 있다. 압전 혹은 자기비틀림 효과를 이용하여 얻는 초음파 진동기는 전기-기계 변환효율이 다른 수단에 비하여 매우 높으므로 이것을 이용하여 얻는 초음파 진동은 왕복운동에서 직선 혹은 회전운동으로 변환시키는 연구가 행해지고 있다. 본 연구에서는 진행파 방식의 초음파 전동기를 중심으로 그 회전 원리를 이해하고 모델링 하였다. 외란에 대하여 강인한 제어방식으로 알려져 있는 가변구조제어의 이론을 이해고 회전형 진행파 방식의 초음파 전동기를 이용한 가변구조, 제어에 의한 서보계를 설계한다. 이때 제어방법은 속도패턴을 미리 정하여 두고 그 패턴에 따라 슬라이딩 모드를 사용하여 속도를 제어하여 위치를 제어하는 것이다. 초음파 전동기의 가변구조제어에 의한 위치제어를 컴퓨터 시뮬레이션으로 검토하고 제어 파라미터를 결정하였다. 그리고 인터페이스 보드를 제작하고 컴퓨터와 전동기를 접속하여 실제 제어 알고리즘을 이용하여 초음파 전동기의 제어 실험을 행하였다.

• Journal of Advanced Marine Engineering and Technology
• /
• v.32 no.8
• /
• pp.1201-1207
• /
• 2008

Numerical analysis information will be very useful to improve fluid system. General information about an internal gas flow is presented by numerical analysis approach. Relating with hydrogen compressing system, which have an important role in hydrogen energy utilization, this should be a useful tool to observe the flow quickly and clearly. Flow characteristic analysis, including pressure and turbulence kinetic energy distribution of hydrogen gas coming to the cylinder of a reciprocating compressor are presented in this paper. Suction-passage model is designed based on real model of hydrogen compressor. Pressure boundary conditions are applied considering the real condition of operating system. The result shows pressure and turbulence kinetic energy are not distributed uniformly along the passage of the Hydrogen system. Path line or particles tracks help to demonstrate flow characteristics inside the passage. The existence of vortices and flow direction can be precisely predicted. Based on this result, the design improvement, such as reducing the varying flow parameters and flow reorientation should be done. Consequently, development of the better hydrogen compressing system will be achieved.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2006.11a
• /
• pp.427-430
• /
• 2006

This paper deals with the internal oscillating flaw in air chamber and duct of an OWC-type wave energy converter by numerical analysis using commercial CFD code, FLUENT. Whole oscillating flaw from OWC-type chamber to outlet through duct was solved by unsteady analysis in order that performance of wave energy conversion was made better. Results show that whole oscillating flaw field of this system in unsteady condition. Duct shape at setting place of turbine is curved with elbow, because profile of inlet condition to turbine is important in its efficiency. This paper is found internal flaw in air chamber and duct. Also, this research was found effect of duct shape.

• Journal of Power System Engineering
• /
• v.13 no.3
• /
• pp.27-32
• /
• 2009

Numerical analysis information of a complex discharge-passage will be very useful to improve hydrogen compression system. General information about an internal gas flow is presented by numerical analysis approach. Relating with hydrogen compressing system, which have an important role in hydrogen energy utilization, this should be a useful tool to observe the flow quickly and clearly. Flow characteristic analysis, including pressure and turbulence kinetic energy distribution of hydrogen gas from cylinder going to the chamber of a reciprocating compressor are presented in this paper. Discharge-passage model is designed based on real model of hydrogen compressor. Pressure boundary conditions are applied considering the real condition of operating system. The result shows pressure and turbulence kinetic energy are not distributed uniformly along the passage of the hydrogen compressing system. Path line or particles tracks help to demonstrate flow characteristics inside the passage. The existence of vortices and flow direction can be precisely predicted. Based on this result, the design improvement should be done. Consequently, development of the better hydrogen compressing system will be achieved.

• Journal of the Society of Naval Architects of Korea
• /
• v.30 no.4
• /
• pp.23-30
• /
• 1993

This rape deals with the experimental and theoretical investigations on the aerodynamic performance of the Wells turbine. The two-dimensional cascade theory is used to estimate the thrust and torque of turbine, and finally to yield an efficiency of turbine. The turbine is assumed to rotate with a constant rotational speed in a sinusoidally varying unsteady flow field. Experimental approach is made in a wave simulator, producing a sinusoidally reciprocating air flow corresponding to the wave motion in an Oscillating Water Column(OWC) chamber. Performance data of turbine measured at various operating conditions are analyzed and compared to numerical results in order to understand the overall features of a Wells turbine.

• KIPS Transactions on Software and Data Engineering
• /
• v.6 no.1
• /
• pp.29-36
• /
• 2017

In this paper, we propose a method for recognizing eating behavior with almost no motion acceleration. First, by using the acceleration of gravity acting on the wrist direction, we calculate the angle between the gravity and the wrist direction. After that, detect wrist reciprocating motion when peak and vally exist in specific angle band. And then, when accumulate the number of wrist reciprocating motion occurrences are up to 10, then regard as the meal time 5 minutes before the detection time. Also, estimate the meal time only if its duration is more than 7 minutes. Using the data of 2128 minutes, which was collected from four graduate student, the result of the meal time estimation shows 95.63% accuracy.

• 한국노년학
• /
• v.29 no.4
• /
• pp.1247-1259
• /
• 2009

Muscle mass is reduced by aging. There seems to be no direct relationship between sarcopenia(muscle loss) and medical cost in the elderly, but lowering muscle mass results in increase risk of fall and decrease of strength, fitness, physical activity, and independent life. This is coupled with physical trouble and chronic degenerative disease such as diabetes, obesity, hyperlipidemia, and hypertension. Thus, sarcopenia is potential risk factor increasing mortality. The purpose of this study was to investigate the effects of elastic band exercise and detraining on sarcopenia prevention related variables, body composition and fitness. The subject of this study was 60~70 aged 14 seniors who participated in exercise program in J-welfare senior center at J-gu in S-city. Elastic band exercise was performed twice per week for 12 weeks. The body composition and fitness variables were measured before 12 weeks of control, after control(before exercise), after 12 weeks of exercise(before detraining), and after 12 weeks of detraining. There was no significant difference in body composition and fitness variables before and after 12 weeks of control, but elastic band exercise before and after 12 weeks has effect on body composition variables such as weight (t=2.978, p=0.001), body mass index (t=3.502, p=0.004), percent body fat (t=2.216, p=0.045), muscle mass (t=-3.837, p=0.002), visceral fat area (t=5.186, p<0.001), and waist-hip ratio (t=3.045, p=0.009) and on fitness variables such as 2-minutes step (t=-6.891 p<0.001), arm curl (t=-4.702, p<0.001), chair stand (t=-4.860, p<0.001), chair sit and reach (t=-5.910, p<0.001), back scratch (t=-3.835, p=0.002), and 8-ft up and go (t=7.560, p<0.001). This exercise effect was continued after 12 weeks of detraining on body composition variables such as weight (t=2.323, p=0.037), body mass index (t=2.503, p=0.026), muscle mass (t=-3.137, p=0.008) and on fitness variables such as 2-minutes step (t=-6.489 p<0.001), chair stand (t=-4.694, p<0.001), chair sit and reach (t=-3.690, p=0.003), and 8-ft up and go (t=7.539, p<0.001). It was found that the elastic band exercise has positive effect on body composition and fitness in the elderly and the effect was maintained over 12 weeks of detraining.