• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.392-400
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• 2001

The sealing performance of an elastomeric O-ring seal using bi-materials has been analyzed for the contact stress behaviors that develop between the O-ring seal and the surfaces with which it comes into contact. The leakage of an O-ring seal will occur when the pressure differential across the seal just exceeds the initial (or static) peak contact stress. The contact stress behaviors that develop in compressed O-rings, in common case of restrained geometry(grooved), are investigated using the finite element method. The analysis includes material hyperelasticity and axisymmetry. The computed FEM results show that the contact stress behaviors are related to a ratio of length between NBR and FFKM and temperature of vaccum chamber.

• Journal of the Korea Safety Management & Science
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• v.24 no.2
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• pp.143-154
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• 2022

Korea has the highest suicide rate in the world, and firefighters have the highest suicide rate among the professional population. As a result of the study, post-traumatic stress disorder education is essential in all occupations. Post-traumatic stress disorder is the most common disease and the biggest obstacle for firefighters in Korea. Firefighters who have suffered physical and mental damage in many types of disaster sites due to their extreme occupations are rapidly increasing the suicide rate in recent years. In order to maximize the effect of job training, education on post-traumatic stress disorder from new employees to leadership training is urgently needed.

• Journal of the Korea Safety Management & Science
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• v.24 no.1
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• pp.21-30
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• 2022

Since the competitive environment, it has become common for firms to reduce its workforce to diminish operating cost. Accordingly, job insecurity among employees has been increasing. Previous works on job insecurity have not paid adequate attention to the influence of job insecurity on safety behavior. The current paper investigates the impact of job insecurity on safety behavior and its intermediating mechanisms. In specific, this paper delves into the mediating effect of job stress, as well as the moderating effect of servant leadership in the association between job insecurity and job stress. The results demonstrated that that job insecurity has a positive (+) influence on job stress, which has a negative (-) influence on safety behavior. Moreover, job stress mediated the association between job insecurity and safety behavior. Furthermore, servant leadership moderated the job insecurity-safety behavior link.

• Korea-Australia Rheology Journal
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• v.18 no.1
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• pp.15-24
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• 2006

The first international inter-laboratory study, involving six laboratories, has been conducted to examine issues associated with yield stress measurements in suspensions. The initial focus of the project was to evaluate the reliability and reproducibility of several common yield stress measuring techniques employed in different laboratories and with different instruments. Aqueous suspensions of colloidal $TiO_2$ at concentrations of 40-70 wt% solids were used as the test fluids. A wide range of instruments and techniques employing both direct and indirect methods were used to determine the yield stress of the samples prepared according to a prescribed procedure. The results obtained indicated that although variations of results existed among different techniques, direct yield stress measurements using static methods produced more reliable and repeatable results than other methods. Variability of the yield stress measured using different techniques within any laboratory however was less significant than variability of the results among different laboratories. The nature and condition of the test suspensions was identified as the most likely factor responsible for the poor reproducibility of yield stress measurements from different laboratories.

• The Korean Journal of Health Service Management
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• v.9 no.4
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• pp.63-78
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• 2015

Objectives : The aim of this study was to examine how emergency medical technicians(EMT) are affected by job stress, musculoskeletal symptoms(MSSs) and depression. Methods : Data were collected from EMTs at emergency medical institutions and fire stations (n=257). With a questionnaire, the association of job stress and MSSs and depression were examined in this study. Results : When examining job stress by place of work, the level of stress in field situations was significantly higher in EMTs at fire stations than in EMTs at emergency medical institutions. The MSSs of EMTs at emergency medical institutions were significantly higher compared to EMTs at fire stations, For depression, the score was 14.09 out of 60, and MSSs were significantly more common in women. Additionally, the level of job stress for 20-24 and over 35 year olds was significantly higher than that in the other age groups. Job stress had a positive correlation with MSSs and depression of EMTs, and MSSs were associated with depression. Conclusions : To improve the work environment of EMTs, attention should be paid to job stress, MSS, and depression and the presence of positive organizational support should be provided which can prevent negative effects.

• Korean Journal of Social Welfare
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• v.56 no.4
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• pp.35-55
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• 2004

Effects of job stress and drinking motivations on the drinking behavior of Korea's mentally challenged in sheltered employment. The purpose of this article was to investigate job stress, drinking motivations, and factors influencing the drinking behavior of Korea's mentally challenged. The 97 subjects' average job stress level was slightly below average. The subjects were found to experience salary-related stress the most out of the five sub-areas of job stress. The strongest motivations of drinking was the social motivation. In terms of drinking behavior, the most common drinking frequency was 3-4 times a year. The most common drinking amount was two 500cc mugs of beer. The significant predictors to explain the variance of the frequency of drinking was motivations to cope with, age, and salary-related stress. The mentally challenged drink more often when they have coping motivations and salary-related stress, and when they are younger. The significant predictors to explain the variance of the amount of drinking was motivations to emotional uplifting, drinking colleagues, stress from role overload. The mentally challenged drink more when they have motivations to emotionally uplift themselves and less role overload-related stress and as they drink alone.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.285-290
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• 2003

Living cells are continuously subject to all sorts of stress such as ultraviolet rays on skin cells. Tests made in various laboratories show that when young fibroblasts (Le. at the beginning of their proliferate life) were repeatedly put under stress at subletal doses, they acquired a phenotype similar to Senescence Induced Prematurely by Stress (SIPS). The work presented hereafter was made on a new model of senescence induced prematurely by stress from ultraviolet Brays (UVB). The human fibroblast model was put under repeated UVB stress, causing SIPS. Several ageing biomarkers were used in order to characterise the cells that underwent stress:. an increase in the proportion of positive cells with senescence associated $\beta$-galactosidase activity (SA $\beta$-gal) measured by a specific coloration,. the proportion in the different morphological stages that fibroblasts undergo during culture visualised by microscopic observation,. the expression of genes known for overexpressing during senescence, particularly fibronectin and apolipoprotein J, measured by Real Time-PCR,. the common deletion of 4,977 bp in mitochondrial DNA, evaluated by nested PCR. Studying the variation of these 4 biomarkers, we have evaluated the protective effect of a Laminaria digitata extract (LDE) that can be used as a natural active ingredient for anti-ageing cosmetics.

• Safety and Health at Work
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• v.6 no.4
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• pp.338-344
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• 2015

Background: The present study aims to investigate job stressors and stress relievers for Korean emotional laborers, specifically focusing on the effects of work conditions and emotional labor properties. Emotional laborers are asked to hide or distort their real emotions in their interaction with clients. They are exposed to high levels of stress in the emotional labor process, which leads to serious mental health risks including burnout, depression, and even suicide impulse. Exploring job stressors and relieving factors would be the first step in seeking alternatives to protect emotional laborers from those mental health risks. Methods: Using the third wave data of Korean Working Conditions Survey, logistic regression analysis was conducted for two purposes: to examine the relations of emotional labor and stress, and to find out job stressors and relievers for emotional laborers. Results: The chances of stress arousal are 3.5 times higher for emotional laborers; emotional laborers experience double risk-burden for stress arousal. In addition to general job stressors, emotional laborers need to bear burdens related to emotional labor properties. The effect of social support at the workplace is not significant for stress relief, unlike common assumptions, whereas subjective satisfaction (wage satisfaction and work-life balance) is proven to have relieving effects on emotional laborers' job stress. Conclusion: From the results, the importance of a balanced understanding of emotional labor for establishing effective policies for emotional laborer protection is stressed.

• Journal of Korean Foot and Ankle Society
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• v.19 no.3
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• pp.128-131
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• 2015

Capsuloligamentous injury at the first metatarsophalangeal (MTP) joint is a common traumatic injury during physical activity, particularly on artificial turf. Mechanism of injury include excessive flexion, extension, or valgus stress. We report a non-operatively treated capsuloligamentous injury at the first MTP joint, which did not occur traumatically but developed by a stress-related mechanism in a collegiate rower.

• Journal of dental hygiene science
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• v.17 no.5
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• pp.439-446
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• 2017

The purpose of this study was to investigate the effect of empathic ability and campus life stress on the stress coping behaviors among 395 dental hygiene students. The analysis was performed using PASW Statistics ver. 18.0, and the following conclusions were obtained. The empathic concern factor was the highest in the subscale of empathic ability (3.60). The interpersonal relationship stress was 1.65 and the task-related stress was 2.72. The stress coping behaviors were the highest among the sub-domains, with 3.69 for wishful thinking. The differences of stress coping behaviors according to general characteristics were as follows. The lower the age and grade, the higher the problem-focused coping; when they were religious there was a high pursuit of seeking social support. When they were satisfied with their economic level, wishful thinking was high. There was a low negative correlation between empathic concern and interpersonal relationship stress in campus life (p<0.01). There was a positive correlation between personal distress and task-related stress (p<0.001). The relationship between empathic ability and stress coping behaviors was most associated with personal distress and wishful thinking. Among the sub-domains of stress coping behaviors, factors that have a common impact on personal distress and seeking social support are viewpoint acceptance. Factors supporting emotional focus and wishful thinking were task-related stress. Dental hygiene students are not able to completely eliminate the stress that they are actually under. However, as the research results show, it is necessary to use stress coping techniques to cope effectively with individual tendencies and situations, and to improve the ability to sympathize with another individual.