• Structural Engineering and Mechanics
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• 제19권2호
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• pp.217-230
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• 2005

A steel silo traditionally consists of a cylindrical and a conical shell. In order to facilitate emptying operations, the cylinder is placed on local supports. This may lead to dangerous stress concentrations and eventually to local instability of the cylindrical wall. In this contribution, the locally supported cylinder is strengthened by means of ring stiffeners and longitudinal stiffeners and the effect of their dimensions on the buckling stress is investigated. This study leads to a number of diagrams, each of them representing the effect of one of the dimensions on the buckling stress. In each diagram, the failure pattern corresponding to the buckling stress is indicated.

• 디지털산업정보학회논문지
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• 제13권3호
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• pp.133-147
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• 2017

This study aims to investigate the effect of personality traits (Big5) of local government officials on job exhaustion. First, we examine the correlation between personal characteristics of individual employees and self-efficacy and the correlation between factors of civil servants' personality characteristics and job stress. Also, it was confirmed whether self-efficacy had a significant effect on job exhaustion and whether job stress had a significant effect on job exhaustion. In order to empirically study this research model, we held a survey based on the employees of Gangnam-gu, Seoul. The main results of this study are as follows : First, it was confirmed that sincerity among personality characteristics affects positive self-efficacy and neuroticism affects negative self-efficacy. However, it was confirmed that extroversion, affinity, and openness were not correlated with self-efficacy. Second, neuroticism has a positive influence on job stress and openness has a negative effect on job stress. However, there was no correlation between extroversion, affinity, sincerity and job stress. Third, the relationship between self-efficacy and job exhaustion turned out to give a negative effect. Finally, job stress was positively influenced by job exhaustion. Therefore, it is necessary to apply the study on personality characteristics (Big5), job stress, and job exhaustion, which have been studied based on service industries, to local government officials. The purpose of this study is to suggest job training for enhancing personality traits that can help reduce the job burden of local government officials.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(III)
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• pp.73-78
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• 2003

The residual stresses and. distortions of structures by welding exert negative effect on the safety of railroad structures. This investigation performs a thermal elasto-plastic analysis using finite element techniques to evaluate residual stresses in butted-welded joint. Considering this initial residual stresses, local stress and strain at the critical location (weld toe) during the loading were analyzed by elastic plastic finite element analysis. Fatigue crack initiation life and fatigue crack propagation life of butt-welded specimen were predicted by local strain approach and Neuber's role and Paris law. It is demonstrated that fatigue life estimates by local strain approach closely approximate the experimental results.

• 보건행정학회지
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• 제33권4호
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• pp.432-439
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• 2023

Background: The purpose of this study is to promote their health by identifying factors that affect the depressive mood experience among local residents in Gangseo-gu, Seoul. Methods: This study is a cross-sectional study analyzed using data from the 2022 Community Health Survey, which is conducted annually in Korea. The subjects of the study were 916 local residents in Gangseo-gu, Seoul. Results: Through this study, the groups with a high level of depressive mood experience among local residents of Gangseo-gu were female, those with low income, those with chronic diseases, those with low subjective health level, and those who perceived their stress to be high. Conclusion: It is necessary for local medical institutions to identify those with low income in blind spots and connect them with community resources to provide necessary economic support. Additionally, regular and systematic management is needed to help local residents prevent and manage chronic diseases. There is a need to actively support local residents by providing stress management programs and various health-related education to local residents so that they can maintain and improve their health and lead healthy lives.

• 터널과지하공간
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• 제27권1호
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• pp.39-49
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• 2017

다양한 암반구조물의 안전도를 정량적으로 표현하는 지수로 안전율이 흔히 사용된다. 그러므로 동일한 응력조건에서 산정된 안전율이라 할지라도 안전율의 정의에 따라 안전율 계산 값의 차이가 있을 수 있으므로 적용하는 안전율의 정의와 특성을 이해하는 것이 중요하다. 이 연구에서는 Mohr-Coulomb 파괴조건식과 Hoek-Brown 파괴조건식을 활용하여 최대전단응력, 최대전단강도, 응력불변량, 최대주응력을 기반으로 하는 4종의 국부안전율을 정의하였다. 이어서 5가지 응력경로에 따른 각 안전율의 변화특성을 고찰하였다. 암반구조물 해석시 전통적으로 많이 이용되고 있는 전단강도 기반의 국부안전율은 최대주응력 및 응력불변량 기반의 안전율에 비해 높은 안전율 값을 계산함을 보였다. 이러한 결과는 보수적 암반공학적 설계가 필요한 경우 전단강도 기반의 국부안전율보다 최대전단응력이나 응력불변량 기반의 국부안전율 도입이 필요하다는 것을 말해준다. 또한 응력경로에 따라 파괴 시 최대주응력 값도 큰 차이가 있을 수 있음을 보였다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2007년도 제28회 춘계학술대회논문집
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• pp.212-216
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• 2007

Predicting microcracking properties of the composite laminates in nonuniform stress conditions was the subject in this paper. The uniform stress field meant the stresses were independent of the width direction. The material was the 954-2A/IM7 laminates containing a central hole. Microcracks initiated at the edge of the hole and propagated into the laminate. Because the tensile stress concentration decreased with distance, the microcracks were arrested before the edge of the laminate. Because carbon fiber composites were opaque, a x-ray method was used to detect the length of the propagating microcracks. The microcracking at the near edge of the hole could be reasonably predicted by considering the local laminate stresses and the microcracking toughness measured in unnotched laminates. However, the date away from the hole did not agree with the predictions. The local microcrack density was always much higher than that predicted by the local laminate stress.

• Computers and Concrete
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• 제16권3호
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• pp.449-466
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• 2015

This paper aims to study the local bond stress-slip behavior of reinforcing bars embedded in lightweight aggregate concrete (LWAC). The experimental variables of the local bond stress-slip tests include concrete strength (20, 40 and 60 MPa), deformed steel bar size (#4, #6 and #8) and coarse aggregate (normal weight aggregate, reservoir sludge lightweight aggregate and waterworks sludge lightweight aggregate). The test results show that the ultimate bond strength increased with the increase of concrete compressive strength. Moreover, the larger the rib height to the diameter ratio ($h/d_b$) of the deformed steel bars is, the greater the ultimate bond stress is. In addition, the suggestion value of the CEB-FIP Model Code to the LWAC specimen's ultimate bond stress is more conservative than that of the normal weight concrete.

• 동서간호학연구지
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• 제16권1호
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• pp.61-69
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• 2010

Purpose: The aim of this study was to identify the correlation among job stress, drinking, and smoking of local government staff. Methods: The participants of this study were 205 government staffs working in a local government office. The data were collected by self-report using questionnaires from March 2 to April 30, 2009. The data were analyzed using t-test, Chisquare test, ANOVA, and Man-Whitney test. Results: Physical stress was the highest in job stress components. Majority of the participants (96%) had drinking experiences more than once per month. 25.4% of respondents reported they drank more than 10 glasses each time. Smoking was habitual in 36.6% of the subjects and 28% of subjects had participation in a smoking cessation program. Respondents who reported high job stress had a longer history of smoking. Conclusions: Job stress was highly associated with drinking and smoking. Stress control programs and smoking and alcohol cessation/moderation programs could be beneficial for the health of government staffs.

• The Journal of Korean Physical Therapy
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• 제2권1호
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• pp.65-74
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• 1990

This study was carried out to measure the degree of work-related stress and to identify factors influencing the excessive stress among clinical physical therapists. One thousand and five physical therapists surveyed nationwide met the established criteria for inclusion in the study. The respondents were an average age of 27.1 years, $34.5\%$ were married, and $61.2\%$ were female. Most of the respondent $(48.1\%)$ worked in local clinics. The average stress score was 50.9. Analysis-of-variance test demonstrated significant difference in the degree of stress among treatment facilities. There was a significant relationship between treatment facilities (general hospital, local hospital, clinic), number of patients treated per day, job satisfaction, low back pain and work-related stress, respectively. Work-related stress was unrelated to matters of sex, marital status, education. Hospital administrators, physical therapydirectors, directors, and individual therapists should work within their organizations to reduce work stress and its detrimental effects. Further research is necessary to investigate preventive measures to decrease the work-related stress.

• Journal of Welding and Joining
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• 제24권2호
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• pp.48-56
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• 2006

The fatigue strength of the welds is affected by such factors as the weld geometry, microstructures, tensile properties and residual stresses caused by fabrication. It is very important to evaluate the structural integrity of the welds in nuclear power plant because the weldment undergoes the most of damage and failure mechanisms. In this study, the fatigue assessments for a reactor vessel outlet nozzle with the weldment to the piping system are performed considering the welding residual stresses as well as the effect of local brittle zone in the vicinity of the weld fusion line. The analytical approaches employed are the microstructure and mechanical properties prediction by semi-analytical method, the thermal and stress analysis including the welding residual stress analysis by finite element method, the fatigue life assessment by following the ASME Code rules. The calculated results of cumulative usage factors(CUF) are compared for cases of the elastic and elasto-plastic analysis, and with or without residual stress and local brittle zone effects, respectively. Finally, the fatigue life of reactor vessel outlet nozzle weld is slightly affected by the local brittle zone and welding residual stresses.