• Journal of Ocean Engineering and Technology
• /
• v.2 no.1
• /
• pp.83-89
• /
• 1988

정지된 유동장에 놓인 반무한 평판이 횡방향으로 갑자기 출발하는 경우에 있어서 평판의 끝에서 발생하는 보텍스의 거동을 해석적 및 수치적 측면에서 검토하였다. 해석적 방법은 단일 보텍스 모델에 근거를 두었으며, 해석결과 순환량은 시간의 1/3승, 보텍스의 중심까지의 거리는 시간의 2/3승에 비례하여 증가함을 알 수 있었다. 룬게.쿠타(Runge-Kutta)방법을 써서 분리 보텍스 모델에 따른 비선형 운동방정식의 해를 수치적으로 구했다. 수치해는 시간의 경과에 따라 해석 해에 접근하였다. 보텍스의 형상에 있어서도 실험결과와 잘 맞았다.

• Journal of the Korean Applied Science and Technology
• /
• v.37 no.1
• /
• pp.91-101
• /
• 2020

The purpose of this study was to investigate the influence of obesity on the expression of autophagy-related proteins in cardiac muscle. To this end, obesity was induced in rats through 20 weeks of high-fat diet, and the animals were then subjected to 8 weeks of treadmill exercise. Subsequently, the expression of proteins that regulate the induction of autophagy, formation of autophagosome, and fusion of autophagosome and lysosome was confirmed. Obesity was induced in the experimental animals (SD rats) through 20 weeks of high-fat diet (carbohydrate: 20%, fat: 60%, and protein: 20%), and they were subsequently subjected to 8 weeks of treadmill exercise (5 days/week, 30 min/day, 5 minutes; 8m/min, 5 minutes; 11m/min, 20 minutes; 14m/min). The experimental groups comprised the normal diet control group (ND-CON, n=10), high-fat diet comparison group (HFD-CON, n=10), and high-fat exercise group (HFD-TE, n=10). Oral glucose tolerance test was conducted before and after 8 weeks of treadmill exercise, and the area under the curve (AUC) was calculated. Through fasting insulin and fasting glucose levels, HOMA-IR, which is an index of insulin resistance, and abdominal visceral fat/body weight (AVF/BW) were calculated for comparison. Moreover, autophagy-related proteins were analyzed from cardiac tissue to investigate the effects of exercise training. Obesity was successfully induced in the HFD-CON group through long-term high-fat diet, and the HFD-CON group had higher body weight, AUC, HOMA-IR, and AVF/BW compared to the ND-CON group. The HFD-TE group, which underwent 8 weeks of treadmill exercise, showed improvements in AUC, HOMA-IR, and AVF/BW. Although the body weight tended to decrease as well, there was no statistically significant difference. mTOR and AMPK, which are involved in the induction of autophagy, both decreased in obesity but increased upon exercise. Beclin-1, BNIP3, ATG-7, p62, and LC3, which are related to the formation of autophagosomes, all increased in obesity and decreased after exercise. Cathepsin L and LAMP2, which regulate the fusion of autophagosome and lysosome, both decreased in obesity and increased upon exercise. Physical activity, including treadmill exercise, was found to induce normal autophagy and improve pathological phenomena observed in metabolic diseases. Therefore, the findings suggest the need to consider treadmill exercise as a primary means to achieve effective prevention and treatment of cardiac diseases.

• Proceedings of the KSCN Conference
• /
• 2004.05a
• /
• pp.434.2-435
• /
• 2004

본 연구는 마우스에 있어 규칙적인 수영훈련과 비타민 C 섭취가 운동스트레스를 부여하였을 때 항산화체계에 미치는 영향을 보고자 하였다. 수영훈련은 6주령의 Balb/c 마우스를 분양받아 1주간의 환경적응과 1주간의 수영적응 훈련을 (30 min/day) (5d/week) 실시하여 적응 여부를 가려 8주간의 본 수영훈련을 실시하였다(1 h/day) (5d/week). 실험군은 통제군(control: C), 수영훈련시킨 군(training: T), 수영훈련과 비타민 C를 투여한 군(training ＋ vitamin C (1.3 g/100 g diet) : TC}으로 나누었다.(중략)

• Journal of Digital Convergence
• /
• v.18 no.8
• /
• pp.493-504
• /
• 2020

The objectives of this study was to examine the effect of Interactive Video Game on cognitive information processing the elderly. Sixty elderly were attended in this study. Their ages ranged from 65 to 70, with a mean age of 67.60 years. The subjects were randomly assigned to one of three experimental conditions: (1) interactive video game group (n=20), (2) aerobic exercise group (n=20), (3) control group (n=20). The experimental design of this study was analyzed using two-way ANOVAs with repeated measures of groups and time. Cognitive function was assessed by neuroelectrical response, and ERP analysis. The results of the study showed that the interactive video game group and aerobic exercise group showed no significant statistical differences in the response time, response accuracy, amplitude and potential of the performance of the exercise in cognitive function and ERP analysis, but improved the interaction video game group and aerobic exercise (walking) group over the control group. It was concluded that long-term aerobic exercise like interactive video game is associated with attenuation of cognitive decline in the elderly.

• Journal of Industrial Convergence
• /
• v.18 no.5
• /
• pp.30-35
• /
• 2020

The purpose of this study is to find out the effect of aerobic exercise through convergence on exhaled carbon monoxide and cardiorespiratory function of female college students who participated in nonsmoking. The subjects were female college students from University D in Metropolitan City D, and those who started smoking 2 years ago and who do not engage in regular physical activities were first selected, and a total of 18 people who indicated their intention to participate in the experiment were selected to receive a pledge of nonsmoking and consent to the experiment. The selected subjects were classified into 9 people in the exercise group and 9 in the control group by wireless assignment, and individual exercise intensity was set through the maximum exercise load test to establish an accurate exercise program. Individual exercise intensity is set to 50%HRmax for 1-3 weeks, 60%HRmax for 4-6 weeks, 70%HRmax for 7-9 weeks. In order to apply the correct exercise intensity during exercise, a Polar heart rate monitor was used for control and the following results were obtained. First, the change in carbon monoxide decreased by three levels from 21.17±3.67ppm (Red 2 16-25ppm, habitual smokers) before participation in the exercise group that participated in aerobic exercise for 9 weeks to 1.36±0.76ppm (Green, 0-6ppm, non-smokers) after participation, and the control group also showed the same effect from 22.35±2.08ppm (Red 2 16-25ppm, habitual smokers) to 2.81±0.51ppm (Green, 0-6ppm, non-smokers). Second, the change in cardiorespiratory function showed a significant increase in all of the maximum oxygen intake, maximum heart rate, and maximum ventilation in the exercise group who participated in aerobic exercise for 9 weeks, but there was no significant change in the control group. Therefore, aerobic exercise showed the effect of improving the cardiorespiratory function by releasing carbon monoxide and supplying sufficient oxygen to various organs.

• Journal of the Korea Convergence Society
• /
• v.8 no.1
• /
• pp.245-256
• /
• 2017

The purpose of this study was to determined the converge effects of combined exercise rehabilitation on lower limb muscular function and cytokines in taekwondo player with patellofemoral pain syndrome. In this study, combined exercise rehabilitation(aquatic exercise 3 times a week, resistance exercise 2 times a week) was performed and 20 collegiate taekwondo player with patellofemoral pain syndrome(control group: n=10, combined exercise rehabilitation group: n=10) were participated for 8 weeks. Statistical significance verification was carried out by a two - way ANOVA repeated measures design as a mixture using the SPSS 18.0 program. The statistically significant level was set at 0.05. The results of this study were as following. Peak torque was higher significantly in extensor(p<.001) and flexor(p<.01) at $60^{\circ}/sec$ in the combined exercise rehabilitation group than the control group over combined exercise treatment period. Average power was higher significantly in extensor muscles at $180^{\circ}/sec$ in the combined exercise rehabilitation group than the control group over combined exercise treatment period.(p<.01). The variable of TNF-a was higher significantly in the combined exercise rehabilitation group than the control group as over combined exercise treatment period. Therefore, it can be concluded that a combined exercise rehabilitation program is effective in improving the lower limb muscular function and TNF-a in Patellofemoral Pain Syndrome patient.

• Journal of the Korean Data and Information Science Society
• /
• v.28 no.1
• /
• pp.109-117
• /
• 2017

This study aims to identify the effect for exercise intensity on hypertension using propensity score based on the sixth Korea National Health and Nutrition Examination Survey data and to provide an evidence for the most effective exercise intensity for prevention or treatment of hypertension. Specifically, we select 3,486 subjects who aged between 18 and 65 years after excluding some subjects who are expected to have limited athletic ability. We estimate propensity scores for exercise intensity based on the confounders such as sex, age, smoking, drinking, and natrium intake. Considering the complex survey design, we conduct a descriptive analysis and multiple logistic regression for hypertension with propensity score as a covariate. Although the results of the study did not show statistically significant relationship between exercise intensity and hypertension, we expect that it can be used as a basis evidence that the appropriate exercise of moderate intensity may be more effective for the prevention and treatment of hypertension rather than strong intensity exercise and non-exercise.

• Journal of Convergence for Information Technology
• /
• v.9 no.8
• /
• pp.260-267
• /
• 2019

The purpose of this study is to find out how underwater rehabilitation exercises affect physical fitness and blood lipids for 10 weeks and provide basic data to help prevent middle-aged women from cardiovascular diseases. The subjects of this study were middle-aged women living in Seoul, Korea. The underwater rehabilitation exercise was performed for 1 week and 3 times for 10 weeks, and the exercise time was 60 minutes for 1 time including the warm up, the main exercise and the cool down. The exercise intensity was set at 60-70% of the heart rate reserve calculated from the pre-exercise test. The measurement variables were physical fitness and blood lipid. In the data processing, descriptive statistics were presented for each measurement item and a 2-way RGRM ANOVA was conducted to examine the interaction effects between groups. The results have shown significant interaction effects in physical fitness(Flexibility, Cardiorespiratory Endurance, Muscular Endurance) and the blood lipids(TG, TC, HLD-C, LDL-C). This study found that the 10-week underwater rehabilitation exercise program of middle-aged women increased physical fitness level and decreased and increased blood lipid, which could be an effective and convergent program to prevent and reduce cardiovascular disease.

• The Journal of the Convergence on Culture Technology
• /
• v.10 no.3
• /
• pp.533-539
• /
• 2024

This study investigated the effects of two exercise programs, which include exercise methods to increase muscle strength, balance, and endurance, on the balance ability and fall efficacy of elderly people, and the differences in effects according to preference. Twenty-one elderly people were divided into a group using assistive devices using elastic bands (Experimental Group 1) and a group using the body (Experimental Group 2) and an exercise program was conducted for 4 weeks. The single leg stand (SLS) and functional reach test (FRT) were used to evaluate the elderly's balance ability, and the fall efficacy scale (FES) was used to evaluate the degree of fear of falling. A pre-evaluation was conducted after a 2-week integrated exercise program, and a post-evaluation was conducted after applying the exercise program for 4 weeks. In the study results, within-group SLS, FRT, and FES analyzes all showed statistically significant improvement in the post-assessment compared to the pre-assessment. However, there were no significant differences in the comparison between groups regarding exercise program and between groups according to preference. In conclusion, in order to increase the balance ability and fall efficacy of the elderly, an exercise program must be applied, and it is necessary to use a program that is easy to apply and includes exercise methods that the elderly can easily perform.

• Journal of Korean Living Environment System
• /
• v.16 no.2
• /
• pp.89-100
• /
• 2009

The present study was designed to observe the thermal dynamics of core and skin temperatures during sub-maximal treadmill exercise; to investigate the effect of regional body cooling during short rest after the treadmill exercise on the thermal dynamics. Three conditions (No cooling, Head/Hand cooling, Leg cooling) were simulated in a climatic chamber at 24±1℃ and 50±5%RH. Subjects performed two bouts of treadmill exercise at a rate of 80%HR_max followed by rest. Body cooling with a hood, long gloves, and a blanket that circulated water set at 15℃ was assigned during two bouts of rest. The results showed that (1) rectal temperature (T_re) did not show significant difference between three conditions; (2) Skin temperatures had specific features, depending on body regions. In particular, the initial fall phenomena of skin temperatures at the onset of exercise were noteworthy in the chest, thigh, calf, and finger tip. Of these, the most significant initial fall was found in finger temperature (T_fing). (3) During the period of the initial fall in skin temperatures, T_re gradually increased. (4) The magnitude of the fall of T_fing at the onset of 2^nd running was on average 4.8, 5.1 and 3.4℃ for Control, HH cooling, and Leg cooling, respectively (p<0.05). The initial drop of T_fing at the onset of running was maintained for an average of 8.1, 7.9 and 6.3 minutes for Control, HH cooling, and Leg cooling, with no significant differences. In conclusion, the initial fall phenomena at the onset of treadmill exercise reflected non-thermal factors, as opposed to internal thermal status. The magnitude of the initial fall in T_fing was affected by legs cooling. Therefore, the initial fall phenomenon should be considered when interpreting the thermal status of the shell during heavy works/exercises that assigned with intermittent regional body cooling.