• 한국산학기술학회논문지
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• 제10권8호
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• pp.1810-1816
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• 2009

2007년도에 9,128건의 화재가 전기적인 원인에 의해서 발생되었고, 이들 화재에 의해 사망 29명과 부상 262명의 인명피해가 있었다. 아크고장은 전기화재의 주요 원인의 하나로, 일반적으로 높은 열을 발생시키며 쉽게 주변의 인화성물질을 점화시킨다. 그러나 기존의 차단기는 과전류, 단락전류, 누설전류에 대해서만 동작하기 때문에, 이에 대해서는 현재 특별한 보호책이 없는 실정이다. 본 논문은 직렬아크 고장전류에 의한 전선의 발화특성에 대한 실험에서 얻어진 결과를 통해 UL에서 제안하고 있는 기준이 국내의 현실에 적절하지 않음을 제시하였고, 이 결과를 기초로 개발된 기술의 동작특성 실험을 실시하여 아크고장회로를 보호할 수 있는지에 대한 신뢰성을 확인하였다. 모의실험을 통한 동작특성 분석결과, 개발된 아크고장 검출 기술을 적용하면 전기화재의 주요원인인 아크고장에 의한 화재를 현저히 저감시킬 수 있을 것으로 판단된다.

• 한국구조물진단유지관리공학회 논문집
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• 제16권2호
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• pp.75-86
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• 2012

본 논문에서는 FR-ECC의 수축특성과 균열도입 전후의 내동해성을 평가하였으며, FR-ECC를 활용한 다층복공구조의 지수성능과 박리박락저항성, 또한 FR-ECC로 단면복구 된 보부재의 휨성능을 평가하였다. 그 결과, FR-ECC는 소성수축에 의한 균열 및 건조수축에 의한 길이변화율이 기존의 보수모르터에 비해 크게 저감되었으며, 구속상태에서의 건조수축에 대한 균열저항성이 개선됨을 알 수 있었다. 또한, FR-ECC는 내동해성이 매우 우수하였으며, 균열도입 후에도 동결융해작용에 의한 인장성능의 저하는 확인되지 않았다. 한편, FR-ECC로 보수된 휨부재는 초기균열모멘트, 항복모멘트 및 극한모멘트 등의 휨성능이 증대되었으며, 멀티플크랙 특성에 의해 휨파괴시까지 균열폭을 안정적으로 제어할 수 있었다.

• Steel and Composite Structures
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• 제9권4호
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• pp.349-366
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• 2009

The composite slim beam has become popular throughout Europe in recent years and has also been used on some projects in China. With its steel section encased in a concrete slab, the steel-concrete composite slim beam can provide the floor construction with minimum depth and high fire resistance. However, the design method of the T-shape steel-concrete composite beam is no longer applicable to the composite slim beam with deep deck for its special construction, of which the present design models are not available but mainly depend on experiences. The elevation of the flexural stiffness and bending capacity of composite slim beams with deep deck is rather complicated, because the influences of many factors should be taken into account, such as the variable section dimensions, development of cracks and non-linear characteristics of concrete, etc. In this paper, experimental investigations have been conducted into the flexural behavior of two specimens of simply supported composite slim beam with deep deck. The emphases were laid on the bonding force on the interface between steel beam and concrete, the stress distribution of beam section, the flexural stiffness and bending capacity of the composite beams. Based on the experimental results, the reduction factor of equivalent stress distribution in concrete flange is suggested, and the calculation method of flexural stiffness and bending capacity of simply supported slim beams are proposed.

• Safety and Health at Work
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• 제2권4호
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• pp.301-312
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• 2011

Firefighters and police officers have the third highest prevalence of obesity among 41 male occupational groups in the United States (US). However, few studies have examined the relationship of firefighter working conditions and health behaviors with obesity. This paper presents a theoretical framework describing the relationship between working conditions, health behaviors, and obesity in firefighters. In addition, the paper describes a detailed study plan for exploring the role of occupational and behavioral risk factors in the development of obesity in firefighters enrolled in the Orange County Fire Authority Wellness Fitness Program. The study plan will be described with emphasis on its methodological merits: adopting a participatory action research approach, developing a firefighter-specific work and health questionnaire, conducting both a cross-sectional epidemiological study using the questionnaire and a sub-study to assess the validity of the questionnaire with dietary intake and physical activity measures, and evaluating the strengths and weaknesses of the body mass index as an obesity measure in comparison to skinfold-based percent body fat. The study plan based on a theoretical framework can be an essential first step for establishing effective intervention programs for obesity among professional and voluntary firefighters.

• 문화기술의 융합
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• 제4권4호
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• pp.429-438
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• 2018

최근 제조업에서 발생하고 있는 사고로 인하여 중대 재해 및 중대 산업사고로 이어지고 지역사회 재난으로까지 확대되는 경향을 나타내고 있다. 안전행정부는 제3차(2015-2019)국가안전관리기본계획에 따라 산업현장 재해 및 재난을 최소화하기 위한 기업재난관리 차원의 개선대책을 발표하고 적극 홍보하고 있다. KOSHA 2015~2017년도의 산업재해 발생 현황을 보면 금속 관련 제조업의 재해율이 1.57%로 전 업종 평균 0.50% 대비 약 3배 이상 높게 나타났다. 재해 원인을 조사해 본 결과 작업자의 불안전한 행동에 기인하여 발생된 비율이 72%로 높게 나타났다. 또한 불완전한 행동은 안전의식과 밀접한 관계를 가지고 있어 이 분야에 종사하고 있는 작업자를 대상으로 안전의식에 대한 설문조사를 실시하였다. 안전의식이 사고 예방에 가장 긍정적인 영향을 미치고 있고 사고발생을 감소시키는 요인으로 나타났다.

• 대한건축학회논문집:계획계
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• 제36권1호
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• pp.27-36
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• 2020

Fifteen years after the modernization of traditional markets, commercial facilities and some 1,000 markets across the country contacted arcade operators, there are no specific guidelines on installation standards, exact guidelines for public facilities, and guidelines on law, maintenance and management yet. Therefore, it is necessary to derive a plan that reflects the mindset of the market project and the users as basic planning data for making arcade remodeling of traditional markets more advanced. As a research method, case studies and surveys were conducted and the details are as follows. Through the case study, this study drew suggestions that were available and needed in Korea on the planning plan of arcade space in the developed traditional market and conducted user preference. The survey participants are 150 users of Daegu seomun market. In addition, the survey contents are approached with the concept of remodeling remuneration, so the total number of questions is 47 including 'accessibility', 'comfort', 'openness', 'safety' and 'integrity', which are five elements of the arcade plan. The survey method assessed the importance and satisfaction of each questionnaire on a 5-point scale, and the survey results were compared with technical statistics and means using the SPSS statistics package. The results of user awareness and image survey, in which the installation and remodeling of the ventilation system of the crosshairs are mentioned in the event of fire or in the case of daily ventilation, are important factors in safety. The user-conscious survey, analyzed in 'integrity', indicates that the use of multi-purpose space is required, and that the layout of street stalls and parking and user movements should be integrated. Mac of this study is going to present direction of remodeling plan and behavior analysis by analyzing user preference data for advanced remodeling of arcade in traditional markets.

• Earthquakes and Structures
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• 제20권1호
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• pp.1-12
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• 2021

The occurrence of progressive collapse induced by the removal of the vertical load-bearing element in the structure, because of fire or earthquake, has been a significant challenge between structural engineers. Progressive collapse is defined as the complete failure or failure of a part of the structure, initiating with a local rupture in a part of the building and can threaten the stability of the structure. In the current study, the behavior of the structures equipped with a cylindrical friction damper, when the vertical load-bearing elements are eliminated, is considered in two cases: 1-The load-bearing element is removed under the gravity load, and 2-The load-bearing element is removed due to the earthquake lateral forces. In order to obtain a generalized result in the seismic case, 22 pair motions presented in FEMA p 695 are applied to the structures. The study has been conducted using the vertical push down analysis for the case (1), and the nonlinear time-history analysis for the second case using OpenSEES software for 5,10, and 15-story steel frames. Results indicate that, in the first case, the load coefficient, and accordingly the strength of the structure equipped with cylindrical friction dampers are increased considerably. Furthermore, the results from the second case demonstrate that the displacements, and consequently the forces imposed to the structure in the buildings equipped with the cylindrical friction damper substantially was reduced. An optimum slip load is defined in the friction dampers, which permits the damper to start its frictional damping from this threshold load. Therefore, the optimum slip load of the damper is calculated and discussed for both cases.

• 한국안전학회지
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• 제36권1호
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• pp.44-49
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• 2021

Domestic industrial accidents continue to increase, with 2,142 deaths in 2018, up by 185 (9.5%) from 1,957 deaths in 2017. Industrial accidents that cause loss of human lives pose a serious risk to businesses because of the strengthening of safety regulations and the changing public perception of social responsibility. Accordingly, to prevent industrial accidents, companies regularly conduct onsite safety activities and conduct education and training to raise awareness among employees. However, many such corporate activities are not conducted voluntarily and practically by employees but mostly by formal implementation. To discontinue this customary and passive behavior of employees and establish a mature safety culture, strengthening the execution power of safety management at the site is of paramount importance, and to this end, we aim to utilize the safety practice index (SPI). In this study, the SPI calculated on the basis of the results of the 2018 and 2019 risk management and safety activities of a site was compared with the reported safety accidents. The results confirmed that the SPI index can be used as a valid indicator for safety activities for accident prevention, such as strengthening leadership and safety policies to grade and manage safety management levels for a certain period of time or by a department or to convert weaknesses into strengths.

• 문화기술의 융합
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• 제8권6호
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• pp.1-7
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• 2022

이 연구는 119 응급 의료 서비스 팀을 위해 설계된 사전 및 사후 교육 실험을 활용하여 분류 교육 프로그램의 효과를 확인하기 위해 수행되었다. 목적: 이 연구는 분류 교육 프로그램에 참여한 119구급대원이 수행한 분류의 정확성에 대한 분류 교육 프로그램의 효과를 평가하였다. 연구 방법: 본 연구의 대상자는 119구급대원 119명으로, 프리젠테이션으로 구성된 20명의 모의환자가 제시되었다. 자료는 SPSS 21.0을 사용하여 분석하였다. 결과: 119명의 응급의료팀의 분류 정확도가 증가한 것으로 나타났다(p<.001). 그리고 과소 분류는 상당한 감소가 나타났다(p<.001). 또한 과대분류는 감소 되었으나 통계적으로 유의하지 않았다. 결론 : 본 연구에서 얻은 결과는 분류 교육 프로그램이 119구급대원의 다발성 부상 환자 또는 재난 피해자 분류의 정확성을 향상시키는데 효과적임을 보여주었다.

• 한국가스학회지
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• 제27권3호
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• pp.134-140
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• 2023

활성탄은 주로 기체나 액체상의 흡착제로 사용되는 탄소질 재료이다. 휘발성 유기화합물의 흡착열 축적 및 산화 등에 의해 화재가 꾸준히 발생함에 따라 석탄과 야자껍질을 원료로 하는 분말 및 입상활성탄을 대상으로 폭발특성 및 열안정성을 평가하였다. 입도분석을 통해 분말활성탄은 입도범위 (0.4~3) ㎛를 가지는 것을 확인하였으며, 시차주사열량계와 열중량분석기를 사용하여 발열개시온도 및 분해거동 등의 열적 특성을 분석하였다. 부유분진에 대한 폭발위험성을 평가한 결과, 석탄계 및 야자계 분말활성탄 모두 St1 등급으로 폭발에 의한 위험성이 약한 분진으로 분류되지만 이는 상대적인 크기를 나타내는 것으로 폭발에 의한 위험성이 절대적으로 작음을 의미하는 것이 아니므로 피해저감을 위한 대책을 수립할 필요가 있다.