• Physical Therapy Korea
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• v.8 no.3
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• pp.11-26
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• 2001

In rehabilitation programs involving muscle re-education and endurance exercise, it is necessary to confirm when fatigue occurs. It is also necessary to quantify fatigue, to confirm whether the muscle has been exercised sufficiently. In general, as fatigue occurs, the force-generating ability of the muscle is reduced. If the median frequency (MDF) obtained from electromyogram (EMG) power spectrum is correlated highly with work, then the timing and degree of fatigue may be confirmed. This study examined the relationship between work and MDF obtained from the EMG power spectrum during repetitive isokinetic exercise. Surface EMG signals were collected from biceps brachii and vastus lateralis of 52 normal subjects (26 males, 26 females) at $120^{\circ}/sec$ and $60^{\circ}/sec$ while performing an isokinetic exercise. The exercise was finished at 25% of peak work. MDF data was obtained using a moving fast Fourier transformation (FFT), and random noise was removed using the inverse FFT, then a new MDF data was obtained from the main signal. There was a high correlation between work and MDF during repetitiv isokinetic exercise in the biceps brachii and vastus lateralis of males and the biceps brachii of females (r=.50~.77). However, there was a low correlation between work and MDF in the vastus lateralis of females (r=.06~.19).

• Research in Community and Public Health Nursing
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• v.14 no.4
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• pp.699-706
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• 2003

The objective of this study is to find out the difference in perceptional fatigue and health promoting behavior between hospital nurses and public health nurses. The subjects of this study were 141 hospital nurses and 73 public health nurses in Daejeon. Data were collected using a self-reporting questionnaire during the period from the 5th to 16th of March 2003. Collected data were analyzed using SPSS program. Real number, percentage, mean and standard deviation were calculated, and $x^2$-test and t-test, ANOVA, Pearson's correlation coefficient, stepwise multiple regression procedures were carried out. The findings of this study as follows: 1. The mean score of health promoting behavior was 2.71. 2. There were statistically significant differences in health promoting behavior according to age, marital status, family status, residency, educational level, income, the length of work experience and the field of work. (p<0.05) 3. There were statistically significant differences in fatigue according to age, marital status, family status, educational level, income, the length of work experience, perceived health status and the field of work. (p<0.05) 4. The fatigue was found to be in significant negative correlations with health promoting (r=-0.358, p<0.000) and self efficacy (r=-0.314, p<0.000). On the contrary, a significant positive correlation was found between fatigue and perceived barriers (r=0.210, p<00.01). 5. There were five predictors affecting health promoting behavior, which were self-efficacy, income, perceived benefit, fatigue and family support. The most influential factor was self-efficacy that made 31% of prediction, followed by income (6%), perceived benefit (5.2%), fatigue (2.2%) and family support (1.7%) in their order. As a whole, these factors made 46.1% of prediction of health promotion behavior.

• Safety and Health at Work
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• v.10 no.2
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• pp.188-195
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• 2019

Background: Mine workers in South Africa face challenges relating to poor health and safety, including fatigue risks, and poor socioeconomic and living conditions. Fatigue results in impaired mental and physical performance. The aim of this study was to assess contributors to fatigue of mine workers in South Africa. Methods: Data collection took place at four gold mines and one platinum mine in South Africa. A total of 21 focus groups were held with individuals in management, union representatives, and mine workers, and 564 questionnaires were completed by mine workers to gather information about fatigue and potential contributors to fatigue at these mines. Results: Qualitatively (through focus groups), fatigue was attributed to extended working hours, harsh working conditions, high workloads, production pressure, and resource constraints, along with aspects relating to demographic and socioeconomic factors, living conditions, lifestyle, health, and wellness. Greater fatigue was significantly associated with younger age, indebtedness, a lack of exercise, poor nutrition, less sleep, increased alcohol use, poor self-reported health, more sick leave, higher stress, and lower job satisfaction. Conclusion: The aim of the study was achieved; numerous work-, sociodemographic-, lifestyle-, and wellness-related factors were linked to fatigue in the participating mine workers. Contributors to fatigue should be addressed to improve health, safety, and sustainability in the industry.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.30 no.3
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• pp.76-85
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• 2022

Work situational awareness test (WSAT) has been utilized to estimate the fatigue risk of workers who worked with time pressure or latent accident risks at their work environment. Thus researchers decided to use WSAT to estimate fatigue risk of cabin crews of an airline in Korea and to analyze empirically how such risk might have an effect on cabin crew's safety behavior. This was because there had not been enough research on accessing cabin crews' fatigue and analyzing its risk for the flight safety. In addition, the mediation effect of cabin crew's planning was also analyzed through Sobel-test by researchers among external factors such as lack of concentration, attention deficit, distraction and safety behavior. According to empirical analysis, it was found attention deficit and distraction of cabin crews due to fatigue during the flight had a significant negative effect on their planning. Planning was also proven to have mediation effect to cabin crew's safety behavior.

• Journal of the Korean Society of Safety
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• v.6 no.4
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• pp.45-52
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• 1991

The purpose of a fatigue crack arrest desing is to prvent a fatigue fracture of machine and structure resulted from unstable crack growth. In all cases of load transfer to second elements such as stringers, doublers or flangers, crack arrest is possible; arrest occuring when the fatigue crack reaches the second element. In the present work, the possibility of crack arrest and the design criterion of fatigue crack arrest in the variable thickness plates are examined numericaiiy by using fatigue crack arrest thresthod $\Delta$K$_{th}$of SA-508 reactor vessel steel and stress intensity factor which was obtained in the previous work as a result of 3-dimensional finite element analysis for CT type variable thickness plates having discontinuous interface.e.

• Journal of Korean Public Health Nursing
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• v.18 no.1
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• pp.103-118
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• 2004

The purpose of this study was to understand the process and investigate basic theory of fatigue experience of shift work nurses. The present study adopted grounded theory methodology on fatigue of shift work nurses. The participants for this study were 15 shift work nurses who were in the age of 25 to 35, the clinical experience of 2 to 14 years and the work department of ICU. ER. ward and delivery room. The data were collected from 2000 to 2003 by using interviews and observations. The contents of the interviews were tape-recorded and were drawn through repeated method. And then were analyzed into the concept, subcategories, and categories with the open coding process and axial coding was done to identify the relationships of the concepts and categories according to the paradigm models. The core category generated, which was a central phenomena of the exhaustion process. The causal condition is change events. The central condition of exhaustion were sorted as physical discomfort, decreasing vigor, psychological instability, feeling of sleeping desire, changing face impression and being heavy body. The intervening condition were discovered as social$\cdot$ psychology$\cdot$physical resist and positive$\cdot$negative interaction strategies. The consequences of the fatigue process is the short term exhaustion relief and long term residual exhaustion. The fatigue process of this study was 'break through exhaustion' of change event-exhaustion-resist-resolve intervention-adaptation. This study offers better understanding on fatigue process of shift work nurses and may facilitate more appropriate interventive strategies to support, information and knowledges according to fatigue process.

• The Korean Journal of Emergency Medical Services
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• v.26 no.1
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• pp.101-118
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• 2022

Purpose: This is a descriptive research study that aims to identify factors affecting fatigue by examining the degree of emotional labor, job stress, and fatigue of 119 emergency medical technicians (119 EMTs). The correlation between emotional labor, job stress, and fatigue was also confirmed. Methods: A total of 139 EMTs working in the Daejeon area participated in this study. Data were collected from July 6-15, 2021. Results: When the number of dispatches was high and the job was dissatisfying, the degree of emotional labor was high. In addition, the shorter the work experience and the lower the job satisfaction are, the higher the job stress is. The degree of fatigue was significantly higher in female than male 119 EMTs, and when they had short work experience and were dissatisfied with their job, the degree of fatigue was higher. Moreover, there was a significant correlation between emotional labor, job stress, and fatigue of the 119 EMTs. Conclusion: To reduce emotional labor, job stress, and fatigue of 119 EMTs, appropriate interventions for each factor and institutional improvements are required.

• Korean Journal of Occupational Health Nursing
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• v.26 no.4
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• pp.261-272
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• 2017

Purpose: The study aimed to identify factors influencing work-life balance in female service workers. Methods: A cross-sectional descriptive study was conducted with an online survey of 234 service workers using volunteer panels. Data were collected using a self-administered questionnaire from July 16 to 24, 2017. Major variables included work-life balance, resilience, emotional intelligence, job stress, and fatigue. Using the SPSS 24.0 program, descriptive statistics, t-test, ANOVA, correlation analysis, and multiple regression analysis were conducted. Results: The mean score of the work-life balance level of female service workers was $2.9{\pm}0.85$ on a total score of 6. A multiple regression analysis revealed that smoking, resilience, job stress and fatigue were statistically significant factors in the model (p<.001), with an explanatory power of 50.3%. Emotional intelligence was not significantly associated with work-life balance. Conclusion: The level of work-life balance was considerably low in female service workers. This study suggests that nursing interventions to enhance work-life balance are required at both the individual and organizational levels.

• Journal of Korea Society of Industrial Information Systems
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• v.6 no.4
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• pp.12-21
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• 2001

Recently, as work strength is deepened, as well, labor environments is changed, simple and iterative worker's Cumulative Trauma Disorders(CTD) is gradually being increased. Accordingly, this study was designed to represent its system design to carry out their iterative and simple task by machine through the difference of muscle fatigue between worker on handling line and worker under the work environments by Air Balance System for the purpose of analyzing their muscle fatigue test according to fulfillment of iterative and simple task. From the result of this study, with regard to the comparison of muscle fatigue between work on handling line and work on automation line on the occasion of refractory brick loading, their muscle fatigue extent under the work environments by Air Balance system was lower than it of handling by AMEG(64.1%), MF(65.3%), MPF(64.3%), ZCR(63.6%) respectively. And also, generally there showed similar transfer at the aspect of muscle mobilization. In other words, we can say that work environments by Air Balance System is beneficial at the aspect of alleviating works' fatigue extent on handling line. As well, the result of this study shows that worker's exposure to Cumulative Trauma Disorders(CTD) is relatively low.

• Journal of Korea Society of Industrial Information Systems
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• v.6 no.3
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• pp.79-86
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• 2001

The CTD(Cumulative Trauma Disorder) as a new kind of occupational disease occurs mainly to workers on handling line under the highly-specialized industrial environments. This study took into account their exposure to Cumulative Trauma Disorders(CTD) by the utilization of EMG system, with respect to worker's muscle fatigue test according to fulfillment of iterative and simple task. The findings of this study were as follows : From the result of AEMG test analysis, worker's fatigue extent according to elapsed time of task was inclined to be increased continually. On the other hand, after its task ending, their fatigue extent was inclined to be decreased than before-circumstance of refractory brick lifting. The transference of MF(Median Frequency) and MPF(Mean Power Frequency) had highly significant difference between muscle fatigue and the elapsed time of work. Especially, their fatigue extent to erectorspinae and multifidus to lift firebrick was increased in the mean time. The transference of ZCR(Zero Crossing Rate) had considerable significant difference between muscle fatigue and the elapsed time of work. In short, as the work went of the muscle fatigue extent increased gradually. Thus, it can be concluded that the fatigue of erectorspinae and multifidus extent according to fulfillment of iterative and simple task is gradually being increased.