• Journal of the Korean Society of Safety
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• v.32 no.2
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• pp.7-13
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• 2017

An experimental study was conducted to identify the quantitative measurement bias for the bare-bead thermocouple (TC), which was widely used for measuring temperature in fire experiments. To this end, an apparatus could be controlled individually gas flow rate, preheating temperature and incident radiative heat flux was developed to simulate the thermal environments of fire. A relative measurement bias of bare-bead TC was evaluated with the comparison of double-shield aspirated TC. As a result, the relative measurement bias of bare-bead TC was gradually increased with the increase in radiative heat flux with constant gas temperature. The relative bias was also significantly increased with the decrease in gas temperature. Quantitatively, at the gas temperature of $20^{\circ}C$, the bare-bead TC had the relative bias of approximately 400% with the radiative heat flux of $20kW/m^2$ corresponding to thermal radiation level of the flashover. The present study was intend to provide fire researchers with methodologies for the reanalyses of temperature measured using bare-bead TC, radiation corrections, and validation of fire modeling.

• Safety and Health at Work
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• v.8 no.4
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• pp.402-406
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• 2017

Transit workers constitute a blue-collar occupational group that have elevated smoking rates relative to other sectors of employed adults in the United States. This study analyzed cross-sectional tobacco survey data from 935 workers (60% African American; 37% female) employed at an urban public transit agency in California. Prevalence of current and former smoking was 20.3% and 20.6%, respectively. Younger workers were less likely than older workers to be current or former smokers. Having a complete home smoking ban was associated with decreased likelihood of being a smoker [odds ratio (OR) = 0.04, 95% confidence interval (CI) = 0.01-0.17], as were neutral views about whether it is easy for a smoker to take a smoking break during their shift (OR = 0.50, 95% CI 0.28-0.88). Current smoking among the sample is > 50% higher than the adult statewide prevalence. Potential points of intervention identified in this study include perceived ease of worksite smoking breaks and establishing home smoking bans. Tailored cessation efforts focusing on older transit workers more likely to smoke are needed to reduce tobacco-related disparities in this workforce.

• Computers and Concrete
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• v.30 no.4
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• pp.257-267
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• 2022

Two different types of rubber aggregates (40 mesh rubber powder and 1-4 mm rubber particles respectively) were devised to substitute fine aggregates at 10%, 15%, 20% and 30% by volume in self-compacting concrete to investigate their basic mechanical properties. The results show that with the increase of rubber content, the reduction of compressive strength, splitting tensile strength and static modulus of elasticity gradually increase, and energy dissipation performance gradually increase. The rubber addition significantly reduces brittleness and decelerates damaged process. Whilst, the effect of rubber particles is greater when they are finer. Considering the mechanical properties, the optimal rubber content is 10%. It is recommended that the rubber volume content in rubberized concrete (RC) should not be higher than 20%. In addition, a constitutive model under uniaxial compression was proposed basing on the strain equivalent principle of Lemaitre and the damage theory, which was in good agreement with the test curves.

• Journal of the Korea Safety Management & Science
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• v.25 no.4
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• pp.87-94
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• 2023

This study analyzed and identified various causes of caustic alarms of 163 fire detectors that occurred from January 2019 to December 2021 at domestic semiconductor manufacturing plants equipped with about 30,000 fire detectors, and proposed a new non-fire prevention cause investigation plan by applying the NFPA 921 scientific methodology. The results of the study are as follows. First, in terms of necessary recognition and problem definition, an analog detector and an integrated monitoring system were proposed to quickly determine the location and installation space information of the fire detector. Second, in order to prevent speculative causes and errors in various analyses in terms of data analysis and hypothesis establishment, non-fire reports were classified into five by factor and defined, and the causes of occurrence by factor were classified and proposed. Finally, in terms of hypothesis verification and final hypothesis selection, a non-fire prevention improvement termination process and a final hypothesis verification sheet were proposed to prevent the cause from causing re-error.

• Safety and Health at Work
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• v.9 no.2
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• pp.140-143
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• 2018

Background: The Occupational Safety and Health Monitoring and Assessment Tool (OSH-MAT) is a practical instrument that is currently used in the German woodworking and metalworking industries to monitor safety conditions at workplaces. The 12-item scoring system has three subscales rating technical, organizational, and personnel-related conditions in a company. Each item has a rating value ranging from 1 to 9, with higher values indicating higher standard of safety conditions. Methods: The reliability of this instrument was evaluated in a cross-sectional survey among 128 companies and its validity among 30,514 companies. The inter-rater reliability of the instrument was examined independently and simultaneously by two well-trained safety engineers. Agreement between the double ratings was quantified by the intraclass correlation coefficient and absolute agreement of the rating values. The content validity of the OSH-MAT was evaluated by quantifying the association between OSH-MAT values and 5-year average injury rates by Poisson regression analysis adjusted for the size of the companies and industrial sectors. The construct validity of OSH-MAT was examined by principle component factor analysis. Results: Our analysis indicated good to very good inter-rater reliability (intraclass correlation coefficient = 0.64-0.74) of OSH-MAT values with an absolute agreement of between 72% and 81%. Factor analysis identified three component subscales that met exactly the structure theory of this instrument. The Poisson regression analysis demonstrated a statistically significant exposure-response relationship between OSH-MAT values and the 5-year average injury rates. Conclusion: These analyses indicate that OSH-MAT is a valid and reliable instrument that can be used effectively to monitor safety conditions at workplaces.

• Fire Science and Engineering
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• v.30 no.5
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• pp.130-136
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• 2016

In this study, the budget investment state of the technology classification structure in a fire-fighting and safety research development program and the capability of a fire-fighting safety research program were analyzed between 2007 and 2013 with support from the ministry of public safety. The Ministry of public safety and security's fire safety research funding has shown a gradual increasing tendency. More 80% of the budget was invested in fire safety and disaster response technologies and the fire safety and special disaster prevention response technology of R&D. From the results of analyzing the capacity of fire-fighting safety and rescue safety, it was found to have a moderate level of 3.5 on a 7 point scale basis. To develop the Ministry of Public Safety and Security's fire safety research in the future, the flexibility and reasonableness of the budget/legal/institutional framework and support should be ensured to improve the operational capability of resources. In addition, a proliferation program is necessary for the commercialization and industrialization of research results.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.214-214
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• 2017

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.99-100
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• 2023

It is proposed that smart construction machinery should be developed to prevent safety accidents at construction sites.

• Korean Security Journal
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• no.3
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• pp.175-204
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• 2000

In modern society, a spontaneous phenomenon that community residents' participation in crime prevention sphere is increasing now due to the recognition that it is extremely difficult to control crime only by the limited official power(police) is spreading in the society. In the consideration of crime occurrence, the fear of crime does not belong to a certain person any more, but it turns to a matter of common interest for all people. If the recognition of community problems is well understood and analysed, the effect of community residents' participation in crime prevention will appear more eminent and definite. For a long period of time, thanks to the community residents' participation in crime prevention, it has been possible to sustain safety and stability of local community. Ultimately not only the police could reduce the crime problems but local community could decrease a fear of crime. In this study, for maximized effect of crime prevention, it is focused on the role of the community residents' participation in crime prevention. For desirable interrelations among service group and residents, police, first the review of situational crime prevention and community crime prevention theory was studied. And the community residents participation to crime prevention activity in U.S.A, Japan etc was reviewed. By interviewing actual participants in community crime prevention activity, the problems and countermeasures of the community residents' participation in crime prevention activity and desirable direction was suggested

• Korean Journal of Child Studies
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• v.20 no.1
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• pp.177-197
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• 1999

The purpose of this study was to provide the basis for establishing policies and recommendations to the legal system to ensure children's safety related to playground equipment and toys. The present legal system, including national inspections and safety requirements were reviewed both in Korea and other advanced countries. Several issues were found related to accident prevention and improvement of playground and toy safety in Korea. Recommendations were made for the development of educational safety programs for children, parents, teachers, consumers, industry, administrators, and policy makers.