• 산업경영시스템학회지
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• 제24권68호
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• pp.1-7
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• 2001

A probabilistic model for fatigue life of a structural component is derived when the component is in a variable-amplitude loading environment. The physical mechanism which governs fatigue failure is used to model the fatigue life. Especially, the judgement of rotational symmetry in the-stress-intensity-factors results in the probability distribution for fatigue life. The probability distribution is related to the familiar truncated Gaussian distribution, which has a single parameter with a direct physical meaning.

• 감성과학
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• 제17권2호
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• pp.85-90
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• 2014

본 연구에서는 업무스트레스 관리를 위해 호흡과 심장박동간의 상관관계를 이용한 최적 호흡법을 유도하고 반복 훈련을 통해 사용자의 건강을 자가 관리하는 시스템을 개발하였다. 일정한 호흡은 심장의 항상성을 유지할 수 있도록 도움을 준다. 심장의 항상성 유지를 통해 업무스트레스 자극으로 인한 심장 리듬의 변화를 빠르게 안정시킬 수 있다. 사람은 개인에 맞는 고유한 호흡리듬을 가지고 있기 때문에, 최적 호흡리듬을 반복적으로 훈련하는 것을 통해 심장의 항상성을 높일 수 있다. 본 시스템은 개인에 맞는 최적 호흡리듬을 찾아서 이를 반복적으로 훈련할 수 있는 시스템을 개발하였다. 그리고 업무스트레스가 높은 콜센터 직원들을 대상으로 검증실험을 실시하였다. 검증실험 결과 자신의 맞는 호흡주기를 사용하여 호흡을 하면 심장의 반응이 안정성을 보이고 부교감이 활성화 되는 것을 확인할 있었다. 개발한 시스템을 활용하면 감정노동자들 중에서 콜센터 상담 업무스트레스를 저감시킬 수 있을 뿐만 아니라, 이를 통한 업무효율증가와 개인의 건강관리에도 많은 도움을 줄 수 있을 것으로 예상된다.

• 대한인간공학회지
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• 제19권2호
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• pp.15-31
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• 2000

The aim was to evaluate the prevailing ergonomic and psychosocial conditions regarding low back injury in an automobile assembly system. This study consisted of two parts. In the first part of the study, analytic biomechanical model and NIOSH guidelines were applied to evaluate risk levels of low back injury for automobile assembly jobs. Total of 246 workers were analysed. There were 20 jobs having greater back compressive forces than 300kg at L5/S1. Also, there were 44 jobs over Action Limit with respect to 1981 NIOSH guidelines. This might in part be explained by the ergonomic conditions of the company analysed generally being good, with a relatively low duration of 'combined' extreme work posture. The relationship between psychosocial factors and low back injury was examined in the second part of the study. It has recently been recognized that overall reaction to working conditions was influenced by a range of factors, some of which were physical and some psychosocial. The psychosocial environment surrounding the work place may contribute to the perception of risk and eventual ill-health. A battery of questionnaires concerning the psychosocial stress based on PWI(Psychosocial Well-being Index) and musculoskeletal pain symptoms at low back was completed by 246 workers at the same plant. Results showed that 207 out 246 workers experienced the symptoms and 27 workers were diagnosed as patients. Two groups(low stressed, high stressed) based on PWI score had no significant relationships with both symptoms and results of diagnosis. However, sensitivities for symptoms and diagnosis by PWI were 91.3% and 92.6% respectively. Finally, relationships between physical work load and psychosocial stress were analysed. Specifically, some postural factors {vertical deviation angle of forearm, horizontal deviation angle of upperarm, vertical deviation angle of thigh, etc) were highly correlated with psychosocial stress. The results illustrated that PWI scores were associated with some physical workloads. However, psychosocial stress levels couldn't be well related with the pain symptom as well as the actual incidence of low back injury since pain or discomfort regarding low back injury were more complex than that of other musculoskeletal disorders.

• 한국직업건강간호학회지
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• 제18권1호
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• pp.106-115
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• 2009

Purpose: Occupational stress is a determinant risk factor for cardiovascular disease and work disability. This study aims to describe occupational stress and identify its related factors among aged security guards. Methods: A random sample of 76 aged security guards were interviewed by three research assistants. The criteria of the subjects were as follows : 50 or older male with 40 or more working hours a week working with colleagues ranged from 3 to 50. The data were collected in September, 2007 and analyzed by multiple regression using SAS Version 9.1. Results: The mean score of occupational stress among aged security guards was 47.2. The mean scores of its sub-scales were 31.3(physical environment), 33.8(occupational demand), 80.8occupational control), 44.6(interpersonal conflict), 51.3 (occupational insecurity), 53.6(occupational system), 57.5(lack of reward), and 30.3(work environment). The scores of occupational control, interpersonal conflict, and occupational insecurity were higher than the scores of Korean average occupational stress sub-scales. Significant variables affecting occupational stress and its sub-scales were work place, work type, and employment type. Conclusion: In order to reduce occupational stress among security guards, sufficient occupational control and interpersonal conflict control, appropriate reward, and employment stability should be considered. Also long working hours and work shift should be improved.

• 경영과정보연구
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• 제25권
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• pp.223-242
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• 2008

Today, businesses are under rapidly changing environments that are characterized as stopless competition and uncertainty. Under this circumstance, workers are exposed to much stress that is induced by factors such as lots of job burden, responsibility, role conflicts, role ambiguity, interpersonal conflicts, pressure related to job performance and lots of job-related requests. Unlike workers of other industries, those of distribution business may be more exposed to stress because they serve in unique work conditions. Therefore, distribution workers have an accumulate fatigue of their own, suffering from health problems that are stress-induced. Distribution businesses should positively try to identify factors that fall their workers into stress, making those workers less stressful and preventing their negative job performance. Efforts to reduce workers' stress can not only improve their physical and mental health, but also raise business competitiveness. Thus the purpose of this study is to investigate how much distribution workers' job role, interpersonal relations and job environment are influential to their job stress and thereon determine relations between job stress and job performance.

• Journal of Oral Medicine and Pain
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• 제32권2호
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• pp.201-210
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• 2007

많은 질병들과 기존에 존재하는 신체적인 질병들은 스트레스로 인해 발병되거나 크고 작은 스트레스의 영향으로 악화된다. 스트레스의 연구에 호르몬을 사용하는 기본은 신체의 대부분 시스템이 스트레스를 받는 동안 변화를 보인다는 것과 이러한 변화에 호르몬이 스트레스와 확실하게 연관되어 있다는 것을 관찰하는 것이다. 개념적으로 스트레스에 있어서 교감신경계와 시상하부-뇌하수체-부신축의 활성화가 중심적인 역할을 한다는 것이 호르몬의 변화를 측정해야 할 충분한 근거를 제공한다. 에피네프린과 노르에피네프린과 같은 카테콜라민, 코티졸, 테스토스테론 그리고 성장호르몬 등은 스트레스에 예민한 반응을 보인다. 한편 스트레스 연구를 위한 타액표본은 혈액이나 요의 표본과는 달리 스트레스를 주지 않고도 표본을 얻을 수 있으며 신체적인 구속이나 윤리적인 문제 등을 염려하지 않고도 채취가 가능하다는 장점이 있다. 타액내의 호르몬의 수치는 혈액내의 호르몬 수치를 잘 반영하므로 스트레스와 관련된 구강안면통증의 연구에 있어서 타액내의 스트레스 호르몬에 활용도는 매우 높으리라고 사료된다.

• 한국치위생학회지
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• 제14권2호
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• pp.131-137
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• 2014

Objectives : The aim of the study is to investigate anxiety, fatigue and stress of dental hygiene students in clinical practice and to improve the psychological support program. Methods : A self-reported questionnaire was filled out by 428 dental hygiene students in 4 universities in Gwagju and Jeonnam. Data were analyzed for anxiety, stress and fatigue, general characteristics using SPSS 18.0 program for descriptive statistics, ANOVA, and correlation. Results : Saliva suction showed the most high score in treatment($mean{\pm}SD=2.92{\pm}1.13$) and was followed by children dental care($2.79{\pm}1.21$), preventive dental care($2.38{\pm}1.04$), maxillofacial radiology($2.35{\pm}1.15$). During the clinical practice, students felt uneasy when they stayed in relative home(p<0.05). Poor interpersonal relation(p<0.001), poor health condition(p<0.01), low satisfaction with major(p<0.01), the other cause of major choice(p<0.01) influenced on their stress. Satisfaction with major was closely related to clinical practice performance, anxiety, physical fatigue and mental fatigue. Conclusions : In order to reduce physical, mental, neuro sensory fatigue of students in clinical practice, it is recommended to reinforce the patient care etiquettes in curricula.

• 한국항공운항학회지
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• 제20권1호
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• pp.76-85
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• 2012

Air traffic controllers often experience fatigue and stress on the job due to work-related factors. Performance impairment resulting from fatigue and stress is an important concern for aviation safety. The goal of this research was to investigate fatigue and stress factors for air traffic controllers. The research involved an extensive literature review of fatigue and stress in the air traffic control environment and surveyed fatigue and job stress level of Korean air traffic controllers compared to other occupation groups. Results of survey showed that fatigue and stress levels of air traffic controllers were significantly higher than other occupation groups. Specially air traffic controllers reported that night work created high level of fatigue and perceived that physical environment and job demand induced high level of stress. In addition, implications for fatigue and stress management were discussed.

• 대한간호학회지
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• 제42권2호
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• pp.269-279
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• 2012

Purpose: To develop a expressive writing program for women with breast cancer and to identify its effects on stress physical symptom, cancer symptom, anxiety, depression, and QOL. Methods: A non-equivalent control pre-post design was used. Participants were recruited from self-help groups in six hospitals and were assigned to the experimental group (29) or control group (29). Data were collected before, after, and at four weeks after the intervention program. Changes in the variables were evaluated to test effects of the developed program, using $X^2$-test, Fisher's exact test, repeated measures ANOVA, and paired t-test. Results: The expressive writing program was developed for women with breast cancer based on Pennebaker's expressive writing. Significant differences were found between the two groups for stress related to physical symptoms ($p$<.00) and quality of life ($p$=.024). No significant differences were found in cancer symptoms, anxiety, or depression between the two groups. Conclusion: The results indicate that the expressive writing program designed to express cancer-related deep thoughts and emotions helps in decreasing physical symptoms and improving QOL. Further studies are needed to identify the effect on emotions such as anxiety and depression for women with breast cancer with above average levels of anxiety and depression.

• 대한인간공학회지
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• 제26권2호
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• pp.45-59
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• 2007

The operating tasks of overhead crane have caused undue stress to the operators from physical, mental, and environmental workload. Existing workload assessment models for musculoskeletal disorders such as OWAS, RULA, and QEC have limited applicability to the crane operating tasks because they focus mainly on physical factors and do not consider the relative importance of each factor. The present study was to develop a workload assessment model customized to overhead crane operation, following a systematic process: (1) analyzing task characteristics, (2) selecting workload factors, (3) developing assessment methods, (4) establishing action levels, and (5) computerizing the assessment model. Based on literature review, worksite survey, and focus group interview, 4 physical factors (awkward posture, static posture, repetitive motion, and excessive force), 6 mental factors (visual demand, auditory demand, task complexity and difficulty, time urgency, work schedule related stress, and safety related stress), and 4 environmental factors (noise, vibration, dust, and temperature) were selected and their rating scales and relative weights were determined. Then, based on the workload assessment results of 8 overhead cranes operated at different workplaces, the action levels of each factor category were established. Finally, the crane operation assessment model was computerized for effective analysis and report preparation. The present approach is applicable to develop a customized workload assessment model for an operating task under consideration.