• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.2
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• pp.232-241
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• 2016

The turbocharger, to decrease the harmful exhaust gas(CO, HC and etc.) and $CO_2$ emission as well as the increase of the engine output, would be an useful method for engine downsizing. Therefore the thermal endurance of turbine blade, the lubrication of turbine shaft and the engine knock according to the supercharge of the inlet air, had been studied. And there had been much progress in these research tasks to be achieved a breakthrough. But a study on the built-in WGV of a gasoline engine for a passenger car which may effect on the engine performance, is few. In this paper, the effect of the embedded WGV on the engine performance was performed through the endurance test, which was conducted more than 300 hrs using the 4 stroke, 1998 cc, water-cooled engine. To sum up the major results, there were an abrasion in the area of the WGV head edge and the thermal deformation on the WGV head face, These phenomena led to reducing the boost pressure which caused the reduction in the volumetric efficiency of the engine. It resulted in decreasing the engine power gradually during the life cycle of the embedded WGV.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.05a
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• pp.143-149
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• 2002

Ball reducer with waved grooves has many advantages over other reducers for the high-reduction ratios, low noise and low energy loss, etc. The mechanism of force transmission is very similar to that of cam and follower in automobile valve train system especially in the contact geometry. In this study, we have investigated the traces of contact between ball and outer race and the working behaviors with a certain reduction ratio. In order to verify the contact behaviors between ball and outer race, which determines the critical endurance life the contact velocity and load are computed for a cycle. During some period of a cycle, the contact velocity reverses its direction very suddenly, which causes undesirable endurance performance of this machinery. From the computational investigation in this work, we hope to predict similar contact damages in other machinery due to this kind of contact behaviors, which is very common in many contact phenomena.

• Korean Journal of Adult Nursing
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• v.14 no.4
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• pp.521-531
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• 2002

Purpose: This study was to identify the meaning of the lived experiences, to describe of the meaning structures and to develop the strategies of nursing intervention centering to these meanings of the smoking cessation. Method: This study was derived from a phenomenological analytic method suggested by Giorgi. The participants in this study were five adults who had the previous experience of smoking cessation. The data were collected from September of 2001 to April of 2002 through systemic interviews and participatory observations. Average of five interviews were performed, and each interview lasted an hour and half. Result: The meaning of smoking cessation was categorized with nine components. That is (1) obstinacy of the habit of smoking ; difficulty of endurance, succumb to temptation of smoking, repetition of smoking and smoking cessation, habit-forming. (2) Bring about a symptom of improving ; took place headache, expectoration of sputum, sense of instability. (3) Waver in worthy ; doubts about smoking cessation, ridiculed smoking cessation. (4) Be narrowed social life ; become estranged from friends. (5) Futility ; unnecessary, harm. (6) Self-repression ; occurred indomitable mind, strong will, endurance. (7) Gratification ; self-admiration, receive praise from family. (8) Delightfulness ; clean in body and clothes, be disgusted with the foul order of smoking. (9) Improvement in welfare ; a clear mind and good memory, improve in health, have a good appetite. Conclusion: The nursing intervention must be focused on these concerns to accomplish successful smoking cessation program.

• Journal of the Korean Wood Science and Technology
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• v.32 no.5
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• pp.66-74
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• 2004

Fire performance is the important criterion for evaluating of safety of wood structures which exposed to the standard fire condition. Endurance time and time-to-failure are used as the criteria for fire performance in many countries. Reliability analysis about wood floor system which exposed to fire was carried out as preliminary research for reliability-based design on fire. Analyses were conducted by two methods, numerical analysis method and deterministic method.. They didn't show the difference between two methods. The reliability of floor exposed to fire showed strong dependence on the coefficient of variation of member and did not be influenced by the strength or load of member.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.2
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• pp.99-107
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• 2009

This study produced a design curve and fatigue limit for a variation in volume ratio and reduction ratio of TiNi/Al composites. In many cases, stress-life curve does not indicate fatigue limit, so it was presented by probabilistic-stress-life curve. Goodman diagram was used to analyze the fatigue strength of materials with a finite life determined by repeated load and the fatigue strength of endurance limit with an infinite life. The fatigue experiment was conducted using the scenk-type plane bending specimen in same shape. The result of the fatigue test, which had been conducted under consistent stress amplitude, was examined. (i) The optimal condition for TiNi/Al in accordance with hot pressing (ii) Impacts of fatigue limit caused by a variation in reduction ratio and volume ratio of TiNi/Al composites (iii) Probability distribution for fatigue limit of TiNi/Al2024 and TiNi/Al6061.

• Molecules and Cells
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• v.22 no.3
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• pp.275-284
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• 2006

The molecular components that generate and maintain circadian rhythms of physiology and behavior in mammals are present both in the brain (suprachiasmatic nucleus; SCN) and in peripheral tissues. Examination of mice with targeted disruptions of either mPer1 or mPer2 has shown that these two genes have key roles in the SCN circadian clock. Here we show that loss of the clock gene mPer2 affects forced locomotor performance in mice without altering muscle contractility. A proteomic analysis revealed that the anterior tibialis muscles of the mPer2 knockout mice had higher levels of glycolytic enzymes such as triose phosphate isomerase and enolase than those of either the wild type or mPer1 knockout mice. In addition, the level of expression of HSP90 in the mPer2 mutant mice was also significantly higher than in wildtype mice. These results suggest that the reduced locomotor endurance of the mPer2 knockout mice reflects a greater dependence on anaerobic metabolism under stress conditions, and that the two canonical clock genes, mPer1 and mPer2, play distinct roles in the physiology of skeletal muscle.

• Journal of Korean Academy of Nursing
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• v.41 no.1
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• pp.80-91
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• 2011

Purpose: This study was conducted to test the effects of a community health promotion project for farmers cultivating garlic. Bandura's self-efficacy theory (1986) and Chaskin's community capacity framework (2001) were used as the theoretical framework. Methods: A nonequivalent control group pretest-posttest design was used. Study participants were 72 garlic farmers (intervention: 36, control: 36). The community health promotion project consisted of health promotion program and community capacity building strategies and was provided for 12 weeks (8 during farming off-season and 4 during farming season). Data were collected between February 23 and May 31, 2009 and were analyzed using chi-square test, Fisher's exact test, t-test, and repeated measure ANOVA using SPSS/WIN 12.0. Results: For the experimental group, significant improvement was found for self-efficacy, farming related health behavior, physical fitness (muscle strength, muscle endurance, upper body flexibility, lower body flexibility, cardiovascular endurance, balance, agility), farmer's syndrome, and health related quality of life as compared to the control group. Conclusion: The findings of the study indicate that the community health promotion project for garlic farmers is effective and can be recommended as a nursing intervention for health promotion of garlic cultivating farmers.

• Journal of Life Science
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• v.15 no.2 s.69
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• pp.220-224
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• 2005

The purpose of the present study is to investigate the effects of long-term exercise program on exercise capacity and cognitive function (MMSE) in male patients with dementia. 24 male patients were divided into two experimental groups : the exercise group (n=12) and the control group (n=12). The exercise group participated in regular exercise program for 12 months, and their exercise capacity (cardiopulmonary function, muscle strength, muscular endurance, flexibility, balance, agility) and MMSE (Mini-mental state examination) levels were evaluated at baseline (pre), after 6 months (mid) and after 12 months (post). The subjects carried on group-exercise of $VO_{2}max\;30\~60\%$, $30\~60$ minute a day, $2\~3$ times per week. Statistical techniques for data analysis was paired samples t-test. The level of statistical significance was ${\le}.05.$ The results of this study were summarized as follows: In the exercise group, there were significant differences in cardiopulmonary function, muscle strength, muscular endurance and MMSE at the times of pre & mid and pre & post, there were significant differences in balance and agility at the time of pre & post only, whereas there was no significant difference in flexibility following the long-term exercise. In the control group, there were no significant differences in all the times. Based on the results of this particular study, one year exercise program increases on the cognitive function & exercise capacity in male patients with dementia.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.3
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• pp.131-140
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• 2015

The purpose of this study is to predict the fatigue life of a planet carrier of a slewing reducer for a tower crane. To predict the fatigue life of the carrier, the inertia endurance test was carried out, and then the input torque profile for the reducer was obtained. The load profile acting on the planet pins that assembled the carrier was calculated from the measured input torque profile using commercial gearbox analysis software. The stress profiles of the carrier weak points were analyzed from the calculated load profile and boundary conditions using commercial FE software, and the stress cycles were determined using the rainflow counting method. Finally, the fatigue life of the carrier was predicted using the equivalent stress range by considering the effect of mean stress, and an S-N curve was drawn up using the GL guideline and the cumulative damage law.

• Women's Health Nursing
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• v.12 no.1
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• pp.37-46
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• 2006

Purpose: The purpose of this study was to investigate the effects of an exercise program on physical function and quality of life of mastectomy patients. Method: This study was conducted from October, 2004 to June, 2005. The subjects consisted of 60 patients with breast cancer(30 each in the experimental and control groups). The subjects in the experimental group participated in an exercise program for 16 weeks. Evaluation was performed four times in both the experimental and control group. Results: The results revealed an increase in physical function in the experimental group including wrist circumstance, function of shoulder joint, stretching, and upper endurance. Also, an increase in function scales in quality of life were significantly higher in the experimental group than the control group. In addition subjective comments on how they felt after participating in the exercise program were good in the experimental group. Conclusion: The 16-week exercise program showed a large positive effect on physical function and quality of life of breast cancer patients after a mastectomy.