• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.833-836
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• 2002

Sometimes open holes are required for the function and the weight reduction of structure and machinery. However, the serious stress concentration occurs because of the geometric discontinuity caused by the holes and cutting section. In this study, it is attempted to obtain the stress concentration coefficients of the inner surface of the hole boundary by changing the position and the shape of holes on the homogeneous isotropic plate. And the effects on the plate are investigated. The results show that the stress level becomes low and the distribution area widens the position of stress concentration changes as the ratio ah increases and change to a circle. And as the ratio a/l decreases, the stress concentration reduces.

• Journal of Korean Academy of Nursing
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• v.34 no.4
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• pp.646-654
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• 2004

Purpose. The purpose of this study was to test the effectiveness of a comprehensive smoking cessation program for Korean adolescents. Method. The study design was quasi-experimental with one pre and three post-tests. The three posttests were done immediately after, three months later, and six months after the completion of the program. A total of 43 high school students who smoked participated in the study with 22 in the experimental group and 21 in the control group. The smoking cessation program consisted of 9 sessions with content on enhancement of self-efficacy, stress management, correction of distorted thoughts, consciousness raising, and assertiveness training. The study variables were urine cotinine levels, self-efficacy, stress, and stages of changed behavior. Results. Urine cotinine levels significantly decreased in the experimental group after the program (F=3.02, p=.06) but significantly increased in the control group (F=6.32, p=.004). Self-efficacy and the degree of stress did not change in either group. The stages of smoking cessation behavior tended to change when compared with raw data for the experimental group. For most participants, the stages of change had been precontemplation and contemplation, but changed to action and maintenance stage among the experimental group. Conclusion. The program was effective in smoking cessation and influencing stages of change but did not change psychosocial factors such as self-efficacy and stress. It is suggested a program should be developed to change psychosocial variables on a long-term basis. It is also desirable to involve peers and families of adolescents who smoke when planning programs to enhance social support.

• Women's Health Nursing
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• v.15 no.1
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• pp.24-31
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• 2009

Purpose: This study was to examine the change of stress and nursing needs in preterm labor women after hospitalization. Method: Forty seven women with preterm labor who were admitted in two university hospitals participated in the survey and they were completed the questionnaires on admission day and 5th day after admission. Questionnaires included in modified Antepartum Hospital Stressor Inventory (AHSI) and Nursing Needs for Preterm Labor. The collected data were analyzed by paired t-test and Pearson correlation test. Result: The stress level was not decreased significantly after hospitalization. Among them, the stresses about fetus and medical staff were decreased significantly after hospitalization, but those about pregnant women, husband and environment were increased significantly after hospitalization. The difference in the level of nursing needs between the two different days was not significant except the physical needs. The total level of stress and nursing needs were correlated significantly on the 5th day after hospitalization. Conclusion: These results indicate that stress and nursing needs of preterm labor women undergo changes after hospitalization. Therefore, development of the program being followed by stressors which change from day to day and further studies are required in order to examine the decreasing of the stress.

• The Journal of Korean Academic Society of Nursing Education
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• v.21 no.1
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• pp.65-74
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• 2015

Purpose: This study was carried outto compare dietary self-efficacy, obesity stress, and obesity-related quality of life (OQOL) according to BMI and stages of change in vegetable consumption. Methods: A convenience sample of 326 nursing students agreed to complete a questionnaire. Data were collected from October 7 to October 18, 2013. Results: Obesity stress and obesity-related quality of life were significantly different according to BMI. Dietary self-efficacy showed a significant difference between the pre-contemplation/contemplation stage, preparation stage, and action/maintenance stage (F=50.18, p<.001). With obesity stress, there was a significant difference between the PC/C, P, and A/M stages (F=17.63, p<.001). Dietary self-efficacy had a positive correlation with OQOL (r=.11, p<.001) and a negative correlation with obesity stress (r=-.14, p=.012). And obesity stress had a negative correlation with OQOL (r=-.45, p<.001). Conclusion: These findings emphasize that nutritional-intervention programs for changes in behavior during the PC/C and P stages of change in vegetable consumption need to develop strategies to enhance dietary self-efficacy for nursing students.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.5
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• pp.126-133
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• 2017

This report investigates the stress distribution according to the location and shape change of the circular hole for the lightweight design of the cross beam of a railway passenger car and studies the lightweight design. To design a lightweight cross beam with a circular hole, we selected the non-circular crossbeam as a basic model, examined the stress distribution and displacement by position and determined the location, shape, size and quantity of the hole for light weight. We analyzed the effects of the position and shape of the hole on the maximum equivalent stress and displacement. The influencing factors were set as the design parameters, and the stress value was examined according to the variation of each variable. By considering the stress value according to the change of each variable and selecting the design parameter with the narrowest scattering value of the stress at each position of the hollow cross beam with various hole positions and shapes, we studied a cross beam with a circle hole under identical load condition to have an equal stress distribution to that of a non-circular cross beam.

• Herbal Formula Science
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• v.11 no.1
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• pp.99-114
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• 2003

This study aimed to investigate the effects of Chaihushugansan and Chaihuyigantang on the change of monoamine-contents in the hypothalamus of mice induced by the immobilization stress. Each formula(1.0g/kg) was injected intragastrically to mice 1 hour prior to the immobilzation stress(15 minutes) before measuring the change of monoamine-contents level in mice hypothalamus. The results were as follows: 1. DA content at control group showed significant change. CHSGS group and CHYGT group showed significant decrease.(P<0.05) 2. NE content of the control group was increased than normal group. NE content of the CHYGT group was shown a significant decrease than control group.(P<0.05) 3. DOPAC contents didn't show significant changes at any groups. 4. 5-HT contents didn't show significant changes at any groups. 5. 5-HIAA contents at CHSGS group and CHYGT group showed signifiant changes.(P<0.05, 0.01) These data revealed that chaihushugansan and chaihuyigantang might have the anti-stress effect through the control of DA and NE contents in the hypothalamus.

• Safety and Health at Work
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• v.11 no.1
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• pp.1-9
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• 2020

Background: As the impact of climate change intensifies, exposure to heat stress will grow, leading to a loss of work capacity for vulnerable occupations and affecting individual labor decisions. This study estimates the future work capacity under the Representative Concentration Pathways 8.5 scenario and discusses its regional impacts on the occupational structure in the Republic of Korea. Methods: The data utilized for this study constitute the local wet bulb globe temperature from the Korea Meteorological Administration and information from the Korean Working Condition Survey from the Occupational Safety and Health Research Institute of Korea. Using these data, we classify the occupations vulnerable to heat stress and estimate future changes in work capacity at the local scale, considering the occupational structure. We then identify the spatial cluster of diminishing work capacity using exploratory spatial data analysis. Results: Our findings indicate that 52 occupations are at risk of heat stress, including machine operators and elementary laborers working in the construction, welding, metal, and mining industries. Moreover, spatial clusters with diminished work capacity appear in southwest Korea. Conclusion: Although previous studies investigated the work capacity associated with heat stress in terms of climatic impact, this study quantifies the local impacts due to the global risk of climate change. The results suggest the need for mainstreaming an adaptation policy related to work capacity in regional development strategies.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.4
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• pp.261-268
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• 2019

Climate change and drought stress are having profound impacts on crop growth and development by altering crop physiological processes including photosynthetic activity. But finding a rapid, efficient, and non-destructive method for estimating environmental stress responses in the leaf and canopy is still a difficult issue for remote sensing research. We compared the relationships between photochemical reflectance index(PRI) and various optical and experimental indices on soybean drought stress under climate change conditions. Canopy photosynthesis trait, biomass change, chlorophyll fluorescence(Fv/Fm), stomatal conductance showed significant correlations with midday PRI value across the drought stress period under various climate conditions. In high temperature treatment, PRI were more sensitive to enhanced drought stress, demonstrating the negative effect of the high temperature on the drought stress. But high CO₂ concentration alleviated the midday depression of both photosynthesis and PRI. Although air temperature and CO₂ concentration could affect PRI interpretation and assessment of canopy radiation use efficiency(RUE), PRI was significantly correlated with canopy RUE both under climate change and drought stress conditions, indicating the applicability of PRI for tracking the drought stress responses in soybean. However, it is necessary to develop an integrated model for stress diagnosis using PRI at canopy level by minimizing the influence of physical and physiological factors on PRI and incorporating the effects of other vegetation indices.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.790-793
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• 2005

In these days, the piezoresistive material has been applied to various sensors in order to measure the change of physical quantities. But the relationship between the sensitivity of a sensor and the position and size of piezoresistor has rarely been studied. Therefore, this paper was focused on the effect of residual stress induced in piezoresistor on the distribution of resistance change ratio and supposed the feasible position of piezoresistor. The resulting are following; The tensile residual stress in the vicinity of piezoresistor decreased the value of resistance change ratio and could not effect on all the area of diaphragm but local area around the piezoresistor. Also, the piezoresistor in the diaphragm type pressure sensor with boss should fabricate in the edge of boss in order to increase the sensitivity of pressure sensor.

• Journal of Nutrition and Health
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• v.28 no.5
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• pp.442-450
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• 1995

This study determined plasma glucose, free fatty acid(ffa), epinephrine, norepinephrine, creatine the phosphokinase(CPK), calcium (Ca), magnesium(Mg) and hydroxyproline, Ca and Mg in the heart muscle. Thirty six male Sprague Dawley rats average weighing 110g divided into two diet group : normal Mg group(0.05% Mg), Marginal Mg group(0.005% Mg). After the rats were on experimental diets for 2 weeks, rats for each group were randomly assigned to stress and no stress group and 30 minutes IMMB stress was administered to stress group every day for two weeks. The following were found : 1) Rats fed normal magnesium diet showed decreased plasma glucose and non signficant change in norepinephrine and CPK with IMMB stress, while magnesium deficient rats showed elevated plasma glucose, norepinephrine and CPK with stress. 2) Myocardial hydroxyproline and plasma epinephrine were not significantly different among groups. 3) In the rats fed adequate magnesium, stress increased plasma magnesium while rats on marginal magnesium diet did not show significant change with stress. 4) Plasma and myocardial calcium were increased in rats fed marginal Mg diet, but did not show any significant difference with stress.