• Geomechanics and Engineering
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• v.19 no.5
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• pp.369-381
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• 2019

The objective of this paper is to study the two dimensional deformation in transversely isotropic thermoelastic medium without energy dissipation due to time harmonic sources using new modified couple stress theory, a continuum theory capable to predict the size effects at micro/nano scale. The couple stress constitutive relationships have been introduced for transversely isotropic thermoelastic medium, in which the curvature tensor is asymmetric and the couple stress moment tensor is symmetric. Fourier transform technique is applied to obtain the solutions of the governing equations. Assuming the deformation to be harmonically time-dependent, the transformed solution is obtained in the frequency domain. The application of a time harmonic concentrated and distributed sources have been considered to show the utility of the solution obtained. The displacement components, stress components, temperature change and couple stress are obtained in the transformed domain. A numerical inversion technique has been used to obtain the solutions in the physical domain. The effects of angular frequency are depicted graphically on the resulted quantities.

• Journal of the Ergonomics Society of Korea
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• v.26 no.3
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• pp.35-43
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• 2007

This study aims at providing some basic material to be made use of for establishing plans through which one can reduce job-related stress, through conducting a survey on the sources of stress and then distinguishing its symptoms by the sources. As the methods of the study, we conducted a questionnaire survey of some selected medium enterprises' employees in the National Capital region and analysed the results. The questionnaire was designed by using the dynamic stress model of Cooper and Eaker and consisted of 85 questions to examine the sources of stress, the characteristics of personalities, and symptoms by each type of stress. The total valid respondents were 392 persons indicating 65.3% of the response rate. For analysing the results, a rating scale was used, and the reliability and validity were tested by using Cronbach's alpha coefficient. As the result of the study, those workers in medium enterprises were found to be put under much stress by responsibility, physical environment factors and career development factors and so on. As physical symptoms of job-related stress, eye fatigue, stiffness in their shoulders, headache, worry or anxiety, and waist ache presented most in the respondents. In addition, as behavioral symptoms, chronic fatigue was most indicated. In organizational symptoms, dissatisfaction about the company and lack of self-motivation for the job performance were found to show most. Moreover, the results indicated that the closer personalities to those appearing in persons mostly of type A they had, the more they were put under intensive stress by the vagueness of their roles and responsibility among all the job characteristics.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.35
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• pp.25-38
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• 1995

The purpose of this study identificate the sources of stress, and then find the influenced factor on the performance of organization by thoses. The sources of stress be limited on the level of individuals and the results of its also be did on the level of organization. The finding of the study will contribute to the effective management of stress by the manager in organization. As a results, rational management would made the quality of life of members of organization to level up, and the goals of organization to achieve rationally.

• Korean Journal of Social Welfare
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• v.60 no.3
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• pp.107-127
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• 2008

This study examined the direct or indirect effects through burnout of sources of work stress of child welfare employees on turnover intentions. In addition, the study investigated the moderating effects of stress coping resources, which was hypothesized to buffer the negative effects of the sources of work stress on burnout. The study data were collected from 190 social workers in foster care services and child protective services. As a statistical method, structural equation model was employed. The study results showed that sources of work stress affect indirectly though raising the level of burnout. The study did not find the moderating effects of stress coping resources. Based on the results, implications for child welfare practice were discussed.

• Journal of the Korean Society of School Health
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• v.9 no.2
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• pp.185-195
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• 1996

This study attempts to discover ways to prevent and cope with stress m primary school students, Specific, ally, we wish to investigate the sources of stress and to identify the variance and frequency of coping methods which have been used by the subjects. After examining the school children's list of items about stress and coping strategies by on open structure method, subjects ranked the seventy of stressor's and frequency of a coping strategies by closed structure method. A survey was done of 720 students who were from the 4th to 6th grade in 4 primary schools in the Chonbuk area from April 1st to May 30th, 1995. The major results obtained from this study were the following. 1. The sources of stress bad were classified in 57 items Among the 57 items, 'were school records' 'illness of parents' 'death of family members' 'meetings with trouble makers' ranked high ranking in the stress ratings. 2. Severity of stress. the mean total stress scores were 186.4 with 285 as the highest score. 3. The kinds of coping with stress using were classified in 35 items, Among the 35 items, 'wandering and walking alone' 'mood getting out of the in any way' 'trying to forget the stressor' 'were among the highest scored. 4. Frequency of coping with stress: mean total stress coping scores were 67.9 with 140 as the highest score. 5. Difference m stress and coping strategies between sex, age, living district and religion groups were examined. 1) Significant variables influencing stress scoring were sex (t=-2,29, p<.001) and grade (F=6.33, p<.001). 2) Significant variables influencing stress coping practice were residence (t=1.94, p<.05), sex (t=-3.17, p<.002) and religion (F=5,95, p<.0001).

• Journal of Preventive Medicine and Public Health
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• v.34 no.2
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• pp.141-148
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• 2001

Objective : To investigate the sources, extent and related factors in South Korean doctors. Methods : The study subjects were 934 doctors in Taegu, Kyungpook Province, Korea(540 independent practitioners, 105 employed at hospitals and 289 residents in training). Information concerning job stress was obtained using a 9-item questionnaire. Information regarding related factors such as demographic characteristics(age, sex, marital status), perceptions on the socioeconomic status of doctors and working conditions(work time, on-call days per week) was also obtained by self-administered questionnaire during April and May, 2000. Results : Major sources of job stress included clnical responsibility/judgement factor, patient factor and work loading factor. The job stress score of residents was the highest among three groups. The score was lower in older doctors. The score was low among those who thought doctors' socioeconomic status was not good. The longer the work time, the higher the job stress score was. Multiple regression analysis was conducted to control for the mutual influence of independent variables. In regression analysis, the score of residents was higher than practitioners. Work time and socioeconomic status perception had negative effects on job stress score. Conclusion : The average job stress score of the doctors was high. Age, work type, working conditions and perceptions of socioeconomic status were found to besignificantly related to job stress score. Although the job stress of doctors is somewhat inevitable due to the nature of the doctor's job, control of work time, development of coping tools and other intervention methods are needed to reduce job stress of doctors. Further studies are required to understand the characteristics of iob stress and reduce the job stress of doctors.

• Safety and Health at Work
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• v.14 no.3
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• pp.325-331
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• 2023

Background: Heat stress is a harmful physical hazard in many occupational settings. However, consequences of occupational heat exposure among workers in a sugarcane factory in Ethiopia are not well characterized. This study aimed to assess the level of occupational heat exposure-related symptoms and contributing factors. Methods: In this cross-sectional study, five workstations were selected for temperature measurement. Heat stress levels were measured using a wet-bulb globe temperature index meter. A stratified random sampling technique was used to select 1,524 participants. Heat-related symptoms were assessed using validated questionnaires. Results: The level of occupational heat exposure was 72.4% (95% CI: 70.2%-74.8%), while 71.6% (95% CI: 69.3%-74.9%) of participants experienced at least one symptom related to heat stress. The most common heat-related symptoms were swelling of hands and feet (78%), severe thirst (77.8%) and dry mouth (77.4%). The identified risk factors were a lack of reflective shields (AOR: 2.20, 95% CI: 1.53, 3.17), not-enclosed extreme heat sources (AOR: 1.76, 95% CI: 1.23, 2.51), a lack of access to shade (AOR: 9.62, 95% CI: 6.20, 14.92), and inappropriate protective clothing provision (AOR: 1.58, 95% CI: 1.27, 2.71). Conclusions: The burden of occupational heat exposure and heat-induced symptoms was high. Lack of reflective shields, the absence of enclosed extreme heat sources, a lack of access to shade, and inappropriate protective clothing provision were considerable attributes of heat stress. Therefore, the use of mechanical solutions to stop heat emissions at their sources and the key factors identified were areas for future intervention.

• Structural Engineering and Mechanics
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• v.31 no.6
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• pp.717-735
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• 2009

The present problem is concerned with the study of deformation of micropolar thermoelastic medium with voids under the influence of various sources acting on the plane surface. The analytic expressions of displacement components, force stress, couple stress, change in volume fraction field and temperature distribution are obtained in the transformed domain for Lord-Shulman (L-S) theory of thermoelasticity after applying the integral transforms. A numerical inversion technique has been applied to obtain the solution in the physical domain. The numerical results are presented graphically. Some useful particular cases have also been deduced.

• Geomechanics and Engineering
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• v.19 no.1
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• pp.29-36
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• 2019

The present research deals with the deformation in transversely isotropic thin circular thermoelastic rotating plate due to time-harmonic sources. Frequency effect in the presence of rotation and two temperature is studied under thermally insulated as well as isothermal boundaries. The Hankel transform technique is used to find a solution to the problem. The displacement components, stress components, and conductive temperature distribution with the radial distance are computed in the transformed domain and further calculated in the physical domain using numerical inversion techniques. Some specific cases are also figured out from the current research.

• Journal of Magnetics
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• v.3 no.4
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• pp.112-115
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• 1998

Possible sources of the stress-anneal-induced anisotropy in FINEMET-type magnets are reviewed and discussed resulting in a conclusion that the most probable origin of this anisotropy is the atomic pair directional ordering. It is also evidence that the anisotropy considered is usually of an easy-plane type.