• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.121-122
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• 2022

Recently, the scale of construction project is getting bigger compared to previous projects. Therefore, the job stress of the field manager responsible for the construction project is getting more and more intense. Therefore, construction companies should establish a job stress management plan for stable human resource management of the field managers. From this perspective, in this study was developed a job stress measurement system in connection with MBTI personality types. The developed system allows the job stress of the field manager to be judged on a scale from 1 to 9 points. Accordingly, it is expected that construction companies will contribute to the effective management of field managers in the future.

• Nuclear Engineering and Technology
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• 제44권3호
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• pp.343-354
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• 2012

Primary water stress corrosion cracking (PWSCC) is a major safety concern in the nuclear power industry worldwide. PWSCC is known to initiate only in the condition in which sufficiently high tensile stress is applied to alloy 600 tube material or alloy 82/182 weld material in pressurized water reactor operating environments. However, it is still uncertain how much tensile stress is re-quired to generate PWSCC or what causes such high tensile stress. This study was performed to pre-dict the magnitude of weld residual stress and operating stress and compare it with previous experi-mental results for PWSCC initiation. For the study, a pressurizer safety nozzle was selected because it is reported to be vulnerable to PWSCC in overseas plants. The assessment was conducted by nu-merical analysis. Before performing stress analysis for plant conditions, a preliminary mock-up ana-lysis was done. The result of the preliminary analysis was validated by residual stress measurement in the mock-up. After verification of the analysis methodology, an analysis under plant conditions was conducted. The analysis results show that the stress level is not high enough to initiate PWSCC. If a plant is properly welded and operated, PWSCC is not likely to occur in the pressurizer safety nozzle.

• 산업경영시스템학회지
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• 제31권1호
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• pp.32-40
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• 2008

According to the statistic of industrial disaster in 2006 presented by the Ministry of Labor, there were 10,235 people with occupational diseases adding 2,740 more people (36.6%) compared to the previous year. Concerning the occupational diseases, 1,607 people had brain-cardiovascular diseases comprising more than 15% of all occupational diseases, and excessive workload and occupational stress seemed to play important parts. According to Korean Society of Occupational Stress, among 7,000 workers at 254 businesses in Korea, 73% of them were reported to be exposed to potential occupational stress and 22% of them were reported to be under severe stress. The increase of occupational stress among workers comes from excessive competition caused by business restructuring, promotion competition, annual salary system and so forth. Occupational stress threatens the heath and even the life of workers and lowers business competitiveness. Using the Korean occupational stress reduction model to the workers at small and medium businesses in Incheon area, therefore, the project intends to measure the level of stress among office workers and examine its relatedness to the VTD subjective symptoms. In addition, the project intends to present some methods to reduce occupational stress and increase business efficiency at work by studying and analyzing the various elements that workers use to reduce their occupational stress.

• 한국환경보건학회지
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• 제50권2호
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• pp.157-167
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• 2024

Background: Several previous studies have shown that commuting is a source of stress for undergraduate students. However, few studies have investigated the effect of commuting on academic stress among undergraduate students, and there has been little awareness of the environmental impact of commuting. Objectives: To evaluate the associations between commute type and/or time and academic stress among undergraduate students in South Korea, focusing on environmental sustainability. Methods: We conducted an online survey and obtained information on commute types, commute times, and academic stress from 510 undergraduate students aged ≥19 years. Academic stress was comprised of five sub-categories of stress, and total academic stress ranged from 5 to 25 points. Multiple linear regression analysis was used to analyze the associations between commute type and commute time and academic stress. Furthermore, the students were grouped into 21 categories based on their transportation mode for commuting. CO₂ emission factors per each commuting category were calculated using the transportation type's CO₂ emission data from previous studies. Spearman's correlation analysis was used to confirm the correlation between CO₂ emission factors and total academic stress. Results: Students using home-to-school transportation without transfers (vs. walking) showed a significantly higher total academic stress of 2.19 points (95% CI: 0.58, 3.80). In contrast, students using school-to-home transportation without transfers (vs. walking) showed a significantly lower total academic stress of 1.96 points (95% CI: -3.55, -0.38). Moreover, students using transportation with lower CO₂ emission factors had lower academic stress scores (home-to-school: correlation coefficient = 0.507, p<0.001; school-to-home: correlation coefficient = 0.491, p<0.001). Conclusions: Our findings suggest that both commute type and time are significantly associated with academic stress among South Korean undergraduate students. When students select environmentally-friendly transportation, they may not only improve their mental health but also improve climate resilience.

• 한국건축시공학회지
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• 제13권5호
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• pp.474-481
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• 2013

The success of a construction project hinges on the effective and efficient management of human resources. The stress of human resources is directly related with work performance, and as such, should be managed to improve work performance. This study examined the correlation between job stress and job satisfaction among building construction project managers. A questionnaire to measure work performance was created by referring to the Korean Occupational Stress Questionnaire Short Form developed by the Korean Occupational Safety & Health Agency, as well as a previous study. The mean job satisfaction score of field managers was 3.6, which suggests that they are generally satisfied in their current job environment. A Pearson's correlation analysis showed that the field managers that were satisfied with their job had less job stress. These results could be used for the effective management of construction site managers and to improve their job performance in the field.

• Journal of Welding and Joining
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• 제15권1호
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• pp.55-65
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• 1997

The stress intensity factor has been calculated for the cracked plate subjected to remote normal stress and reinforced with a plate by symmetric spot welding. The solution was based on displacement compatibility condition between the cracked sheet and the reinforcement plate. It is shown that the results from the derived equation for stress intensity factor were agreed with previous solutions. The reinforcement effect gets better as a joining spot is closer to the crack tip and the other joining spots become nearer to the crack surface.

• 대한기계학회논문집
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• 제19권5호
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• pp.1229-1242
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• 1995

The thermal shock stress intensity factors of semi-elliptical surface crack in finite plate and the stress intensity fractors of embedded elliptical crack in turbine rotor is determined by means of Vainshtok weight function method. In case of semi-elliptical surface crack, the solution is compared with previous solution. The stress intensity factor for embedded elliptical crack in turbine rotor loaded by centrifugal and thermal loading is also determined. In this case, the value of stress intensity factor is larger at crack contour near internal radius surface and is almost constant at the crack contour farther from internal radius surface.

• 한국광학회:학술대회논문집
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• 한국광학회 2000년도 제11회 정기총회 및 00년 동계학술발표회 논문집
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• pp.214-215
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• 2000

As silica based optical fibers and preforms are processed at a high temperature, residual stresses are bulit in the strucure when cooled down to the room temperature. The magnitude of the residual stress depends on the difference in the thermal expansion coefficients between core and cladding glass as well as on the temperature difference. Residual stress distribution determines the intrinsic strength and could affect the long term reliability of optical fibers. And furthermore, stress can introduces anisotropy into optical fibers by photoelastic effects. The analysis of thermal stress has been intensively studied for multimode fibers$^{(1)}$ and the authors and co-wokers recently reported the stress distribution in a depressed inner cladding structure$^{(2)}$ . The compositions of the glass in the previous studies, however, have been restricted to conventional glass formers, such as GeO2, B2O3, P2O5, Fluorine. (omitted)

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집A
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• pp.176-181
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• 2000

Stress intensity factors for a rigid line inclusion tying along a bimaterial interface are calculated by the boundary element method with the multiregion and double-Point techniques. The formula between the stress intensity factors and the inclusion surface stresses are derived. The numerical values of the stress intensity factors for the bimaterial interface rigid line inclusion in the infinite body are proved to be in good agreement within 3% when compared with the previous exact solutions. In the finite bimaterial systems, the stress intensity factors for the center and edge rigid line inclusions at interface are computed with the variation of the rigid line inclusion length and the shear modulus ratio under the biaxial and uniaxial loading conditions.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.88-93
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• 2008

Weld overlay is one of the residual stress mitigation method which arrest crack. An overlay weld sued in this manner is termed a preemptive weld overlay(PWOL). PWOL was good for distribution of residual stress of dissimilar metal weld(DMW) by previous research. Because range of overlay welding is wide relatively, residual stress distribution on PWR is affected by welding sequence. In order to examine the effect of welding sequence, PWOL was applied to a specific DMW of KORI nuclear power plant by finite element analysis method. As a result, the welding direction that from nozzle to pipe is better good for residual stress distribution on PWR.