• Title/Summary/Keyword: Impact Safety

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차량 충격 시뮬레이션을 통한 복합소재 교량용 방호울타리의 성능 분석 (Performance Evaluation of Composite Safety Barrier for Bridge by Vehicle Impact Simulation)

  • 김승억;전신열;홍갑의;이민철
    • 한국전산구조공학회논문집
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    • 제24권5호
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    • pp.499-506
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    • 2011
  • 본 연구에서는 컴퓨터 시뮬레이션을 통해 복합소재 교량용 방호울타리의 성능을 분석하였다. 복합소재 방호울타리는 SB4등급을 선정하였다. 복합소재의 적층을 고려하기 위해 LS-DYNA에서 제공하는 재료모델 MAT58을 사용하였다. 복합소재는 섬유와 수지의 종류 및 섬유의 방향에 따라 성능이 상이하다. 수지는 폴리우레탄, 섬유는 유리섬유를 사용하였다. 본 논문에서는 섬유의 방향성이 다른 3가지 적층 설계안에 대해서 충돌 시뮬레이션을 수행하여 성능을 비교 평가하였다. 실차충돌 실무 업무편람에 따라 구조적 강도성능, 탑승자 보호성능, 충돌 후 차량의 거동, 가드레일의 비산에 대한 성능 평가를 실시하였다. 그 결과 적층 설계의 횡 방향 섬유의 양이 많아질수록 충돌 시뮬레이션에서 더 좋은 성능을 나타내었다.

Environment Assessing for Airborne Radioactive Particulate Release-introduction of Methods in IAEA Safety Report Series No.19

  • Meng, Dan;Yang, Liu;Shen, Fu;Yang, Yi;Ma, Yinghao;Ma, Tao;Zhang, Zhilong;Fu, Cuiming
    • Journal of Radiation Protection and Research
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    • 제41권4호
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    • pp.409-417
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    • 2016
  • Background: Airborne radioactive particulate in many important nuclear facilities (particularly nuclear power plants) will have a strong impact on the relative public dose if they are released into the corresponding environment traversing the stack or vents. The radiation protection researchers have regarded the relative environment assessing and estimation of public doses. And the model of assessing impact of discharges radioactive substance to the environment have been recommended by many international organizations (e.g. IAEA) with the nuclear energy safety and radiation protection. Materials and Methods: This paper introduced the generic models that were suggested by International Atomic Energy Agency (IAEA), for use in assessing the impact of discharges of radioactive substances to the environment (e.g. IAEA Safety Report Series No.19). Results and Discussion: The writers of this paper, based on the recommend methods, assessed the discharge limits in some airborne radioactive substances discharging standards. The reasons that IAEA method are introduced are mainly the following considerations: IAEA is one of international organizations with some authorities in the nuclear energy safety and radiation protection; and, more important, the recommend modes are operational methods rather than the methods having little operations such as that have used by some researchers. Conclusion: It is wish that the introduced methods in this paper can be referenced in draft or revise of the standards related to discharges of radioactive substances to the environment.

SM490A의 FCAW 용접 자세별 형상에 관한 기계적 특성 연구 (A Study on the Mechanical Properties of SM490A by FCAW Welding Attitude)

  • 임광묵;이성일
    • 한국안전학회지
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    • 제34권6호
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    • pp.7-12
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    • 2019
  • Flux Cored Arc Welding (FCAW), which has been widely used in many industries, was developed in the 1950s to supplement shortcomings of the Shielded Metal Arc Welding (SMAW). FCAW has an advantage in that it can weld regardless of postures and give good quality results in the filed with many different working conditions. In this study, SM490A (rolled steel for welding structural purpose) with different thicknesses (L:25T+R:30T) were welded using FCAW. Then the mechanical properties (tension test, bending test, hardness test, impact test and macro test) were analyzed and the following conclusions were drawn. In the tensile test, it exceeds the KS standard tensile strength range (400~510) in all welding positions, which means there is a problem in the tensile force transmission performance. In the bending test, it was found that most of the specimens did not exhibit surface rupture or other defects during bending test and they exhibit sufficient toughness even after plastic deformation. In the hardness test, all the results were lower than the standard value of 350 Hv of KS B 0893, which means they have good hardness. In the impact test, all results were larger than the KS reference value of 27J. In the macro test, they showed uniform structure state by the shape of the weld, and there was risk of lamination because no internal defects, bubbles, or impurities were found on the surface of the weld.

Fear of COVID-19 and Its Impact on Job Satisfaction and Turnover Intention Among Egyptian Physicians

  • Abd-Ellatif, Eman E.;Anwar, Manal M.;AlJifri, Abobakr A.;Dalatony, Mervat M. El
    • Safety and Health at Work
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    • 제12권4호
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    • pp.490-495
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    • 2021
  • Introduction: The risk of experiencing psychiatric symptoms related to the COVID-19 pandemic is high among healthcare workers whose occupations are in public health, emergency medicine, and intensive or critical care. Materials and methods: A cross-sectional study aimed to assess the prevalence of fear of COVID-19 among 411 frontline Egyptian physicians during the COVID-19 pandemic; identify determinants and predictors for fear of COVID-19; determine the impact of fear of COVID-19 on job satisfaction; and detect the impact of fear of COVID-19 on turnover intention. Three standardized scales (fear of COVID-19, job satisfaction, and turnover intention scores) were used for data collection via online Google Form. Results: Regarding fear relating to the COVID-19 pandemic, 16.5% of the study subjects were classified as experiencing a severe fear level, while 78.1% experienced a moderate degree. A significant association between the level of fear relating to COVID-19 and the work department. The highest degree of fear is in a general-educational-university facility. Regarding job satisfaction, 42% of those having a severe level of fear are dissatisfied. Fear of COVID-19 is negatively associated with job satisfaction while positively significant correlated with turnover scores, a positive significant predictor of turnover intention. Job satisfaction is negatively associated with turnover intention; a negative significant predictor of turnover intention. Conclusions: Frontline Egyptian physicians reported higher levels of fear relating to the COVID-19 pandemic (moderate to severe). Increased fear levels relating to COVID-19 have a relationship with lower levels of job satisfaction and higher levels of job turnover.

Analysis of Relationship between Construction Accidents and Particulate Matter using Big Data

  • Lee, Minsu;Jeong, Jaewook;Jeong, Jaemin;Lee, Jaehyun
    • 국제학술발표논문집
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    • The 9th International Conference on Construction Engineering and Project Management
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    • pp.128-135
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    • 2022
  • Because construction work is conducted outdoors, construction workers are affected by harmful environmental factor. Especially, Particulate Matter (PM10) is one of the harmful environmental factors with a diameter of 10㎍/m3 or less. When PM10 is inhaled by human, it can cause fatal impact on the human. Contrary to the various analyses of health impact on PM10, the research on the relationship between construction accidents and PM10 are few. Therefore, this study aims to conduct the relative frequency analysis which find out the correlation between construction accidents and PM10, and the modified PM10 grade is suggested to expect accidents probability caused by PM10 in the construction industry. This study is conducted by four steps. i) Establishment of the database; ii) Classification of data; iii) Analysis of the Relative Frequency of accidents in the construction industry by PM10 concentration; iv) Modified PM10 groups to classify the impact of PM10 on accident. In terms of frequency analysis, the most accidents were occurred in the average concentration of PM10 (32㎍/m3). However, we found that the relative frequency of accident was increased as the concentration of PM10 increased. This means the higher PM10 concentration can cause more accidents during construction. In addition, PM10 concentration was divided as 6 groups by the WHO, but the modified PM10 grade by the relative frequency on accident was suggested as 3 groups.

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공군 전투조종사의 임파워링 리더십, 지시적 리더십, 안전의사소통 및 안전행동과의 관계: 안전동기의 조절된 매개효과 (The Relationship between Empowering Leadership, Directive Leadership, Safety Communication, and Safety Behavior for Air Force Combat Pilots: The Moderated Mediating Effect of Safety Motivation)

  • 공만석;박지영;신용환;손영우
    • 한국항공운항학회지
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    • 제26권2호
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    • pp.8-30
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    • 2018
  • The purpose of this study was to investigate the relationship between empowering leadership, directive leadership, safety communication, and safety behavior. Also, we examined whether safety motivation had a moderated mediating effect on this relationship. We collected the surveys from 343 combat pilots of the Republic of Korea Air Force for the analysis. Our structural equation modeling analysis revealed that there was a positive relationship between empowering leadership and safety behavior, and safety communication fully mediated the relationship. However, there is no relationship between directive leadership and safety behavior. Also, our results showed that safety motivation moderated the relationship between empowering leadership and safety communication, but not the relationship between directive leadership and safety communication. Furthermore, the relationship between empowering leadership and safety behavior through safety communication varied significantly with the degree of safety motivation, such that the higher the safety motivation, the higher the impact of empowering leadership on safety behavior through safety communication. Finally, we discussed the implications of these results, study limitations, and practical suggestions for future research.

항공운항학과 재학생의 성향, 안전행동, 비행 의사결정에 관한 연구 (An Study on Propensity, Safety Behavior and Aeronautical Decision-making of Student Majoring in Flight Operation)

  • 김근수;김하영
    • 한국항공운항학회지
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    • 제28권3호
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    • pp.52-60
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    • 2020
  • The purpose of this study was to analyze the effects of Student Majoring in Flight Operation's propensity, safety behavior and aeronautical decision-making. According to the analysis results, First, parents' criticism of perfectionism factor is found to have a negative effect on safety behavior. Second, student pilot's proactive personality has a positive impact on both safety participation behavior and safety compliance behavior. Third, both safety participation behavior and safety compliance behavior are found to have a significant effect on situation awareness, solution generation and solution implementation of decision making stages. Therefore, this study is intended to provide useful basic data that can be applied to studies such as appropriate psychological counseling, optimal training directions and teaching methods in order to cultivate excellent human resources through safe flight training.

Occupational Injury Prevention Research in NIOSH

  • Hsiao, Hongwei;Stout, Nancy
    • Safety and Health at Work
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    • 제1권2호
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    • pp.107-111
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    • 2010
  • This paper provided a brief summary of the current strategic goals, activities, and impacts of the NIOSH (National Institute for Occupational Safety and Health) occupational injury research program. Three primary drivers (injury database, stakeholder input, and staff capacity) were used to define NIOSH research focuses to maximize relevance and impact of the NIOSH injury-prevention-research program. Injury data, strategic goals, program activities, and research impacts were presented with a focus on prevention of four leading causes of workplace injury and death in the US: motor vehicle incidents, falls, workplace violence, and machine and industrial vehicle incidents. This paper showcased selected priority goals, activities, and impacts of the NIOSH injury prevention program. The NIOSH contribution to the overall decrease in fatalities and injuries is reinforced by decreases in specific goal areas. There were also many intermediate outcomes that are on a direct path to preventing injuries, such as new safety regulations and standards, safer technology and products, and improved worker safety training. The outcomes serve as an excellent foundation to stimulate further research and worldwide partnership to address global workplace injury problems.

"잡 크래프팅이 안전을 만든다." : 직무 과부하가 안전 행동에 미치는 영향 ("Job Crafting Makes Safety": The Effect of Work Overload on)

  • 김병직
    • 대한안전경영과학회지
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    • 제24권1호
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    • pp.81-89
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    • 2022
  • Since the competitive environment, work overload among employees has been increasing. The purpose of this paper is to investigate the impact of work overload on safety behavior and its intermediating mechanisms. In specific, this paper delves into the mediating effect of job stress, as well as the moderating effect of job crafting in the association between work overload and job stress. To empirically test the hypotheses, this study utilized survey data from 168 Korean employees by conducting structural equation modeling(SEM) analysis. The results demonstrated that work overload has a positive (+) influence on job stress, which has a negative (-) influence on safety behavior. Moreover, job stress mediated the association between work overload and safety behavior. Furthermore, job crafting moderated the work overload-safety behavior link.

안전보건정보 제공이 일용근로자의 주관적 건강인식에 미치는 영향 (The Impact of Occupational Safety and Health Information on Precarious Workers' Self-rated Health )

  • 노현승
    • 한국산업보건학회지
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    • 제33권4호
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    • pp.471-484
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    • 2023
  • Objectives: This study aimed to confirm the relationship between occupational safety and health information and self-rated health among precarious workers. Methods: A cross-sectional explanatory study design was conducted using data from the Korea Occupational Safety and Health Agency's 6th Korean Working Conditions Survey. The participants were 1,569 precarious workers living in South Korea. Descriptive statistics, t-test, ANOVA, Pearson correlation analysis, and hierarchical regression were used for data analyses by SPSS (version 25.0). Results: As a result of the study, occupational safety and health information had a significant positive effect on the self-rated health of precarious workers. The results suggest that occupational safety and health information contributes to the self-rated health of precarious workers. Conclusions: Therefore, it is suggested that policies should be developed to improve occupational safety and health information in workplaces. In addition, strategies should be developed to promote the usefulness of occupational safety and health information to precarious workers.