• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.5
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• pp.110-117
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• 2001

In the weldments, the crack propagation rate is changed due to the residual stress. The crack propagation rate is high in the region with the residual stress. However it shows the same behavior with the base metal in the region that does not include the residual stress. The fatigue crack growth rate for the material with residual stresses can be predicted more precisely by using the effective stress ratio. The difference between experimental results and prediction results seems to be due to the redistribution of the residual stresses and microstructural change.

• Journal of the Korean Society of School Health
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• v.19 no.2
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• pp.25-36
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• 2006

Purpose : To investigate academic stress, coping method, and stress symptoms of high school students. Methods : Four hundreds-forty five high school students were studied from 14th July to 21th July, 2006. All subjects were in 1st, 2nd and 3rd grade of two high school in Seoul. The academic stress, coping method and stress symptoms were evaluated by questionnaire. Results : Male students showed more academic stress than female students. There was a significant difference in the academic stress according to sex. The 2nd grade students show the highest score of academic stress in the 3 factors(parents, teacher, and friend). Male students used more active coping methods to academic stress than female students. There was a significant difference in the coping methods to academic stress according to sex. There were positive correlations between the academic stress and the stress symptoms. Among the academic stress factors, parents and teacher factor influenced physiologic, psychologic, and behavioral symptom of stress symptoms. The friend factor influenced psychologic and behavioral symptom of stress symptoms. Conclusion : According to the study results, we must provide high school students more effective coping methods to academic stress at school environment.

• Journal of Korean Clinical Health Science
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• v.7 no.2
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• pp.1345-1354
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• 2019

Purpose: This study aimed to determine the mediating effects of aggressive stress response on the association between clinical practice stress and clinical practice satisfaction in ophthalmic optics majors and provide basic data that could help form opticians' professionalism and make clinical practice more effective. Methods: This study was conducted in 236 sophomores and juniors in Daegu and North Gyeongsang Province who had finished clinical practice. Hierarchical regression analysis and mediating effect testing were performed to determine the associations among clinical practice stress, clinical practice satisfaction, and aggressive stress response and determine the mediating effects of aggressive stress response on the association between clinical practice stress and clinical practice satisfaction. Results: Clinical practice stress was significantly negatively correlated with clinical practice satisfaction and aggressive stress response (p<0.01), and aggressive stress response was significantly positively correlated with clinical practice satisfaction (p<0.01). The association between clinical practice stress and clinical practice satisfaction was more likely to be explained by the addition of clinical practice stress than by being aggressive stress response controlled, which statistically significantly met the criteria for mediating effects (p<0.001). Conclusions: It is necessary to pay more attention to program development and teaching methods within the department of ophthalmic optics so that ophthalmic optics majors can utilize aggressive stress response to overcome clinical practice stress effectively and improve clinical practice satisfaction.

• Korean Journal of Health Education and Promotion
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• v.20 no.3
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• pp.91-108
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• 2003

Psychological stress is a growing issue in work stress research because work stressors are closely related to depression； and depression, in turn, decreases organizational effectiveness. Considering such causal relationships of work stress, a comprehensive source to control work stress is needed for worksite mental well-being. This study was conducted to identify how social support at work controlled work stress and which characteristics of social support were effective on work stress reduction. The study participants were 240 workers employed in a public hospital in Georgia, U.S.A self-administered survey was given to employees with their pay slips, and followed by a hospital wide voice reminder for 7 days. Surveys were conducted over a 20-day period. The questionnaires asked about job demands, job control, social support at work, depression, job performance, absenteeism, and demographics. The social support construct was structured on the source of support at work and the kinds of support were provided. Statistical analyses were conducted in the structural equation modeling approach. Social support at work was directly related to high job control, low depression, and high job performance. High score of social support at work were significantly associated with high job control, low depressive symptoms, and high job performance. By source of support, only organizational support was positively related to high job control. Organizational support was more effective than supervisor and coworker support. Any stressors and their outcomes were not differenciated by the kinds of support. This result indicated that job control was influenced more by the source of support than the kinds of support provided at work； and the most efficient source of support was the organization. Organizational support was a strong factor in improving workers" perceived controllability of their jobs from a work stress reduction perspective.tive.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.5
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• pp.952-958
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• 1988

To analyze the nonflatness and residual stress in accelerated cooled plate, a numerical analysis model has been developed. Two factors, i.e. temperature and phase transformation, are considered in calculating the stress distribution that develops during cooling. The plastic strain and plate-buckling, which are often shown in accelerated cooled plate, were determined from this stress. Mean temperature in through thickness direction and temperature difference in width direction are considered in the model to simplify the calculation. The temperature and stress distribution changes caused by phase transformation are involved in terms of the effective specific heat and the effective thermal expansion coefficient. With the model, accelerated cooling of 10mm(t) $^{*}$3000mm(w) plate was simulated. The condition of accelerated cooling was .deg. C/sec from just after hot rolling to 500.deg. C. The initial temperature-difference ratio, .DELTA.Tr, in width direction is an important factor in evaluating the stress distribution. When .DELTA.Tr is 0.08, buckling occurs during cooling and 7kgf/m $m^{2}$ of residual stress develops at the edge of plate. To secure the flatness, .DELTA.Tr should be less than 0.07. Small scaled cooling test was conducted to verify the exactness of the model and the results proved the usefulness of this numerical analysis model.l.

• Stress
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• v.25 no.4
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• pp.239-245
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• 2017

Background: A quasi-experimental study with non-equivalent control groups was performed to determine an effect of aromatherapy foot bath on stress and autonomic nervous activity. Methods: To confirm the effect of aromatherapy foot bath, aromatherapy foot bath group was asked to have a bathing by dropping 0.5 cc in 18 L water after blending with a ratio of 6:3:1 with essential oil lavender, lemon, and tea tree and a foot bath group was asked for bathing only by water. Results: Aromatherapy foot bath group showed significant decrease in subjective stress score (t=3.465, p=0.001) and stress index (t=3.021, p=0.004) in addition to simultaneous increase in sympathetic nervous activity (t=-2.913, p=0.005). However, no significant stimulation of parasympathetic nervous system was observed (t=-1.831, p=0.072). Conclusions: As aromatherapy foot bath is a possible effective intervention for stress relief, it can be applied as an effective method to relieve the stress for healthy adults and patients.

• Journal of Industrial Convergence
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• v.19 no.1
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• pp.87-97
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• 2021

This study aimed to systematically review the literature on the stress reduction of meaning-centered therapy (MCT) studies in Korea and to identify the characteristics of MCT for stress reduction. MCT studies aimed at reducing stress symptoms were searched among peer reviewed journal articles and unpublished dissertations until April, 2020. Two independent researchers assessed the risk of bias and the quality of the report using Scottish Intercollegiate Guidelines Network criteria. As a result of searching with 7 databases, 7 studies were finally selected. Seven MCTs were for all age groups, and 5 studies reported MCT was effective in reducing stress symptoms. Both single and combined type interventions were effective in reducing stress symptom, Researchers used the combined MCT more than single MCT program. The study with no significant effect was related to school test stress. There is a need to develop MCTs suitable for school-age youth with test stress in the future.

• Journal of East-West Nursing Research
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• v.23 no.1
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• pp.86-95
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• 2017

Purpose: This study was conducted to investigate the effects of forest walking program on stress and recovery among schizophrenic patients in a closed ward. Methods: A non-equivalent control group pre-posttest design was used. The participants were composed of 36 patients with schizophrenia admitted in two psychiatric hospitals. The experimental group (n = 18) received the forest walking program twice a week with a total of 6 weeks. Results: The study results revealed that the forest walking program was effective on stress(${\chi}^2=34.11$, p<.001), subjective recovery(${\chi}^2=22.40$, p<.001) and clinical recovery(F=28.34, p<.001) of hospitalized patients with schizophrenia. Conclusion: The findings indicate that the forest walking program for schizophrenic patients in the closed ward can be an effective nursing intervention to reduce stress and improve recovery ability. We suggest that mental health nurses may adapt this program to help patients with schizophrenia in a closed ward.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.14 no.4
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• pp.455-467
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• 2001

In this study, the stacking phase shift effect on the effective property and stress distribution was investigated for 8-harness satin weave textile composites under uni-axial tension. Textile configurations with varied phase shifts were modeled by unit cells and repeating boundary conditions were applied at the outer periodic surfaces. The effective property and stress were calculated by the unit cell analysis using macro-element to reduce the computational resource. It was found that stresses were dependent on the variation of tow arrangement of adjacent layers. The in-phase and the shifted configurations showed large differences in the stress distribution pattern. The stress level was very high in the resin region and the distribution of the maximum stresses was widely scattered.

• Korean Journal of Adult Nursing
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• v.19 no.3
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• pp.353-364
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• 2007

Purpose: The purpose of this study was to investigate the effects of health promotion program on physiological stress, perceived stress and menopausal symptoms in menopausal women. Methods: This study followed a nonequivalent control group pretest-post test design. The subjects consisted of 57 middle-aged women(30 in the experimental group and 27 in the control group) who were recruited from the community health center in J city. The subjects in the experimental group participated in a health promotion program for 8 weeks, which was composed of yoga and teaching for 1 session per week. Results: The health promotion program showed a statistical difference in blood pressure, pulse rate and perceived stress. However, there was not a statistical difference in serum cortisol, or menopausal symptoms. Conclusion: This health promotion program was partially effective for reducing stress and it was not effective for reducing menopausal symptoms in menopausal women. It is necessary to conduct a future study using a different time period, measurement time, and target population.