• Transactions of the Korean Society of Mechanical Engineers
• /
• v.15 no.2
• /
• pp.693-702
• /
• 1991

The existence of residual stress in the circumferential butt welded pipes is one of the most important problems concerning stress corrosion cracking in service. In this paper, the residual stress distributions in three kinds of circumferential butt welded pipes were measured by the hole drilling strain gage method and calculation using finite element method is performed and its results are compared with the experiments. At the inner surface of the pipe region near the center line of welding is under high tensile residual stress. However, as the distance from the center line of welding increases, the tensile component decreases and finally becomes compressive residual stress at region far away from the center line of welding. The longitudinal residual stress at the outer surface is compressive regardless of the diameter of pipe and the circumferential stress is changed rom compressive to tensile as pipe diameter increases. The results also demonstrate that the residual stress is mainly caused by self restraint bending force in the pipe welding.

• Korean Journal of Occupational Health Nursing
• /
• v.26 no.3
• /
• pp.125-132
• /
• 2017

Purpose: This study was performed to identify the impact of aggressiveness of patients and a sense of coherence on posttraumatic stress in psychiatric nurses. Methods: After collecting data from 162 psychiatric nurses, we carried out a t-test, ANOVA, Pearson's correlation coefficient, and multiple regression using IBM SPSS Statistics 19.0. Results: The mean score of posttraumatic stress was $20.75{\pm}16.59$ points. Verbal aggression, aggressiveness about property, aggression toward oneself, and aggression toward others had a positive correlation with posttraumatic stress, while a sense of coherence had a negative correlation with post-traumatic stress. It was concluded that the significant predictors of posttraumatic stress in psychiatric nurses were aggression toward oneself, a sense of coherence, and aggression toward others, all of which accounted for 38.9% of the variability. Conclusion: The results of this study indicate that the factors influencing posttraumatic stress in psychiatric nurses were aggression toward oneself, aggression toward others, and a sense of coherence. Therefore, education programs should be developed in consideration of the fact that aggressive behavior against the patient himself and against others intensify the posttraumatic stress of the psychiatric nurse, but the integration force mitigates it.

• Journal of Korean Academy of Nursing
• /
• v.34 no.8
• /
• pp.1491-1498
• /
• 2004

Purpose. This study was conducted to compare the paternal rearing behavior and rearing stress level between fathers with a preschooler and fathers with school children so that it can be utilized as a basic source for developing parental rearing education programs. Methods. A descriptive comparative methods was conducted to identify the paternal rearing behavior and paternal rearing stress. Respondents were 361 fathers who had either preschoolers (n=189) or children of elementary age (n=l72). Results. Comparing the two group's means, the rearing activity score and rearing stress there were significant differences. In the school children's group's father, 'outdoor activity' and 'guidance on discipline activity' were significantly higher than the other group. In the preschool children's fathers group, 'play interaction activity' was statistically significant higher than the other, and the child-part mean score of paternal rearing stress was significantly higher than the other group. The correlation between paternal rearing behavior and paternal rearing stress, it can be shown that more paternal rearing behavior means less paternal rearing stress. Conclusion. These results of this study will help design rearing program for fathers that have either preschool children or school children by providing the basic data for paternal rearing behaviors and paternal rearing stress.

• Korean Journal of Child Studies
• /
• v.33 no.2
• /
• pp.111-127
• /
• 2012

This study compared a number of related variables according to children's stress types using the data mining method. The sample population was taken from the Korean Youth Panel Survey (KYPS) data (2688, sixth-grade elementary students). The results of the decision tree model revealed that : (1) Parental expectations in terms of study, life satisfaction, self-esteem, parental attachment, aggression, the spousal relationship, other cognition (one's own misdeeds), and study related worries were all related to parent stress. (2) Life satisfaction, study related worries, admitting one's own misdeeds, gender, other cognition (one's own misdeeds), aggression, the spousal relationship, and a sense of alienation in the school were all related to appearance stress. (3) Study related worries, parental expectations in terms of study, aggression, life satisfaction, self-esteem, parental attachment, satisfying parental expectations, parental attachment, and teacher attachment were all related to academic stress. (4) A sense of alienation in the school, mixing with peers in the school, aggression, self-esteem, other cognition (one's own misdeeds), study related worries, parental abuse, and life satisfaction were all significantly related to friend stress. These results suggested that children's diverse conditions should be considered according to the stress types if we are to understand and cope with these stress types more efficiently.

• The Journal of the Society of Korean Medicine Diagnostics
• /
• v.19 no.1
• /
• pp.35-45
• /
• 2015

Objective The aim of this study was to investigate stress-related factors. Method: The subjects were 22,937 persons who had received health examination by Korean Medicine and submitted questionnaires for 8 months from March to November in 2011. The stress was measured by heart rate variability in an automobile manufacturing industry. We analyzed the relationship between stress and other factors including ages, smoke amount, drinking frequency, exercise frequency, occupational category, conjugal condition by multivariate analysis with SPSS ver. 19.0. Results: Comparing "normal" to "very bad" and "bad" level of stress, ages, drinking frequency, conjugal condition are not significant difference(p>0.05). But smoking amount and occupational category are significant difference(p<0.05). Whereas comparing "normal" to "very good" and "good" level of stress, ages, occupational category, conjugal condition, smoking amount, drinking frequency are not significant difference(p>0.05). Exercise is significant difference(p<0.05). Conclusion: The results of this study suggest that smoke is affected to stress negatively, whereas exercise is affected to stress positively.

• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.54 no.2
• /
• pp.45-50
• /
• 2005

To improve mean-life and reliability of power cable, in this study, we have investigated electrical properties and stress-strain showing by changing the content of carbon black that is semiconductive additives for underground power transmission. Specimens were made of sheet form with the nine of specimens for measurement. Volume resistivity of specimens was measured by volume resistivity meter after 10 minutes in the pre-heated oven of both 25±1 [℃] and 90±1 [℃]. And stress-strain of specimens was measured by TENSOMETER 2000. A speed of measurement was 200[mm/min], ranges of stress and strain were 400[Kgf/㎠] and 600[%]. In addition tests of stress-strain were progressed by aging specimens in air oven. From this experimental results, volume resistivity was high according to increasing the content of carbon black. And yield stress was increased, while strain was decreased according to increasing the content of carbon black. And stress-strain were decreased some after aging because of oxidation reaction of chemical defect. We could know EEA was excellent more than other specimens from above experimental results.

• The Journal of Korean Academic Society of Nursing Education
• /
• v.22 no.4
• /
• pp.452-461
• /
• 2016

Purpose: This study was conducted to investigate the relationships among communication competence, professional self-concept, and stress in clinical practice of nursing students. Methods: The study participants were 308 senior year nursing students in D city and K province. Collected data were analyzed using t-tests, analysis of variance, Pearson's correlation coefficient, and stepwise multiple regression with the SPSS Version 20.0. Results: There were significant differences in participants' stress of clinical practice based on their level of satisfaction on clinical practice, self-confidence of nursing and difficulty with relationships in clinical practice. A negative correlation was detected between stress in clinical practice and the professional self-concept of nursing students. Significant predictors of the perceived stress of clinical practice were satisfaction in clinical practice and pride in nursing. These accounted for 18% of the perceived stress of clinical practice in a regression model. Conclusion: The results may serve as basic data in support of the need to the develop effective systematic stress management programs and clinical training courses in order to attenuate the stress experienced during clinical practice of nursing students.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.28 no.7
• /
• pp.977-985
• /
• 2004

An evaluation of fatigue life of welded components is complicated due to various geometrically complex welding details and stress raisers in vicinity of weld beads, ego under cuts, overlaps and blow holes. These factors have a considerable influence on the fatigue strength of welded joints, as well as the welding residual stress which is relaxed depending on the distribution of local stress at the front of the stress raisers. To reasonably evaluate fatigue life, the effect of geometries and welding residual stress should be taken into account. The several methods based on the notch strain approach have been proposed in order to accomplish this. These methods, however, result in differences between analytical and experimental results due to discrepancies in estimated amount of relaxed welding residual stress present. In this paper, an approach that involves the use of a modified notch strain approach considering geometrical effects and a residual stress relaxation model based on experimental results was proposed. The fatigue life for five types of representative welding details, ego cruciform, cover plate, longitudinal stiffener, gusset and side attachment joint, are evaluated using this method.

• Journal of Korean Clinical Nursing Research
• /
• v.22 no.1
• /
• pp.38-45
• /
• 2016

Purpose: The purpose of this study was to understand the effects of verbal violence experience, social support, and coping patterns on job stress among operating room(OR) nurses. Methods: The participants were 214 operating room nurses in general hospitals. Data were collected from April 1st to May 1st in 2013 and were analyzed using a multiple regression. Results: The most influencing factor on job stress for OR nurses was verbal violence experience from doctor(${\beta}=.35$), and verbal violence experience from nurse (${\beta}=.27$) followed. Social support from co-workers was a significant factor in decreasing job stress (${\beta}=-.22$). Those three factors explained 43.0% (F=54.76, p<.001) of OR nurses' job stress. Conclusion: The findings of this study revealed that doctors' and nurses' verbal violence increased job stress of OR nurses and social support from co-workers was found decreasing OR nurses' job stress. The results of the study provides an necessity for developing an effective program for minimizing job stress of OR nurses caused by work place verbal violence.

• Journal of the Korean Society for Heat Treatment
• /
• v.5 no.4
• /
• pp.201-208
• /
• 1992

An experimental study of the constitutive response of precipitation-strengthened Al-0.55wt% Zr alloy, which consists of an Al matrix precipitation-strengthened by coherent particles, ${\beta}^{\prime}(Al_3Zr)$ with $L1_2$ structure has been performed. The deformation response of the materials has been examined by stress relaxation test at 573K, 623K and 673K. It was found that there exist the threshold stress during stress relaxation and threshold stress results from the presense of ${\beta}^{\prime}(Al_3Zr)$ particles. The ratio of threshold stress and Orowan stress decreased gradually with increasing temperature. The resistance to climb-pass of particles was independent of particles size for a fixed volume fraction although the threshold for bowing and particles cutting are sensitive to the particles dimensions. The smaller particles cutted by dislocations. This behavior of dislocations in this alloy was explained in terms of the small value antiphase boundary energy. The dislocation networks wrere more extensive in spesimens subjected to stress relaxation and there were numerous areas that have a high denstiy of jogged dislocation. This experiment results indicate that the rate controlling stress relaxation process is the climb of edge dislocation over particles.