• 제목/요약/키워드: Fire school

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동일열량공급하의 밸브오버랩기간 변화에 대한 역화억제 검토 (A Investigation of Back Fire Control with Valve Overlap Period Change In the Same Supply Energy)

  • 강준경;;노기철;이종태
    • 한국수소및신에너지학회논문집
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    • 제18권3호
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    • pp.348-355
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    • 2007
  • To grasp a feasibility of back fire control by valve overlap period, back fire limit equivalence ratio was estimated with valve overlap period which has the same supply energy and positive intake pressure as valve overlap period $300^{\circ}\;CA$. As the result, it was shown that the smaller valve overlap period has the higher back fire limit equivalence ratio under valve overlap period $300^{\circ}\;CA$ as well as VOP $0^{\circ}\;CA$. This result means that expansion of back fire equivalence ratio by decreasing valve overlap period was caused by decrease of back flow duration of flame from in-cylinder to intake port than decrease of lower supply energy.

Development of an Improved Loop-Mediated Isothermal Amplification Assay for On-Site Diagnosis of Fire Blight in Apple and Pear

  • Shin, Doo-San;Heo, Gwang-Il;Son, Soo-Hyeong;Oh, Chang-Sik;Lee, Young-Kee;Cha, Jae-Soon
    • The Plant Pathology Journal
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    • 제34권3호
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    • pp.191-198
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    • 2018
  • Fast and accurate diagnosis is needed to eradicate and manage economically important and invasive diseases like fire blight. Loop-mediated isothermal amplification (LAMP) is known as the best on-site diagnostic, because it is fast, highly specific to a target, and less sensitive to inhibitors in samples. In this study, LAMP assay that gives more consistent results for on-site diagnosis of fire blight than the previous developed LAMP assays was developed. Primers for new LAMP assay (named as DS-LAMP) were designed from a histidine-tRNA ligase gene (EAMY_RS32025) of E. amylovora CFBP1430 genome. The DS-LAMP amplified DNA (positive detection) only from genomic DNA of E. amylovora strains, not from either E. pyrifoliae (causing black shoot blight) or from Pseudomonas syringae pv. syringae (causing shoot blight on apple trees). The detection limit of DS-LAMP was 10 cells per LAMP reaction, equivalent to $10^4$ cells per ml of the sample extract. DS-LAMP successfully diagnosed the pathogens on four fire-blight infected apple and pear orchards. In addition, it could distinguish black shoot blight from fire blight. The $B{\ddot{u}}hlmann$-LAMP, developed previously for on-site diagnosis of fire blight, did not give consistent results for specificity to E. amylovora and on-site diagnosis; it gave positive reactions to three strains of E. pyrifoliae and two strains of P. syringae pv. syringae. It also, gave positive reactions to some healthy sample extracts. DS-LAMP, developed in this study, would give more accurate on-site diagnosis of fire blight, especially in the Republic of Korea, where fire blight and black shoot blight coexist.

Experimental and numerical studies on the shear connectors in steel-concrete composite beams at fire and post fire exposures

  • Mirza, Olivia;Shil, Sukanta Kumer;Rashed, M.G.;Wilkins, Kathryn
    • Steel and Composite Structures
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    • 제39권5호
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    • pp.529-542
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    • 2021
  • Shear connectors are required to build composite (concrete and steel) beams. They are placed at the interface of concrete and steel to transfer shear and normal forces between two structural components. Such composite beams are sensitive to provide structural integrity when exposed to fire as they loss strength, stiffness, and ductility at elevated temperature. The present study is designed to investigate the shear resistance and the failure modes of the headed stud shear connectors at fire exposure and post-fire exposure. The study includes ordinary concrete and concrete with carbon nanotubes (CNTs) to build composite (concrete-steel) beams with structural steel. Experimental push tests were conducted on composite beams at ambient and elevated temperatures, such as 200, 400 & 600℃. Moreover, push tests were performed on the composite beams after being exposed to 200, 400 & 600℃. Push test results illustrated the reduction of ultimate shear capacity and stiffness of headed stud shear connectors as the temperature increased. Although similar values of ultimate shear were obtained for the headed stud connectors in both ordinary and CNT concrete, the CNT modified concrete reduced the concrete spalling and cracking compared to ordinary concrete and was observed to be effective at temperatures greater than 400℃. All specimens showed a lower shear resistance at fire exposures compared to the corresponding post-fire exposures. Moreover, numerical simulation by Finite Element (FE) analyses were carried out at ambient temperature and at fire conditions. The FE analysis results show a good agreement with the experimental results. In the experimental studies, failure of all specimens occurred due to shear failure of headed stud, which was later validated by FE analyses using ABAQUS.

Beliefs of University Employees Leaving During a Fire Alarm: A Theory-based Belief Elicitation

  • Christopher Owens;Aurora B. Le;Todd D. Smith;Susan E. Middlestadt
    • Safety and Health at Work
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    • 제14권2호
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    • pp.201-206
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    • 2023
  • Background: Despite workplaces having policies on fire evacuation, many employees still fail to evacuate when there is a fire alarm. The Reasoned Action Approach is designed to reveal the beliefs underlying people's behavioral decisions and thus suggests causal determinants to be addressed with interventions designed to facilitate behavior. This study is a uses a Reasoned Action Approach salient belief elicitation to identify university employees' perceived advantages/disadvantages, approvers/disapprovers, and facilitators/barriers toward them leaving the office building immediately the next time they hear a fire alarm at work. Methods: Employees at a large public United States Midwestern university completed an online cross-sectional survey. A descriptive analysis of the demographic and background variables was completed, and a six-step inductive content analysis of the open-ended responses was conducted to identify beliefs about leaving during a fire alarm. Results: Regarding consequence, participants perceived that immediately leaving during a fire alarm at work had more disadvantages than advantages, such as low risk perception. Regarding referents, supervisors and coworkers were significant approvers with intention to leave immediately. None of the perceived advantages were significant with intention. Participants listed access and risk perception as significant circumstances with the intention to evacuate immediately. Conclusion: Norms and risk perceptions are key determinants that may influence employees to evacuate immediately during a fire alarm at work. Normative-based and attitude-based interventions may prove effective in increasing the fire safety practices of employees.

조립식 건축물의 화재특성연구 (An Experimental Investigation on Combustion Characteristics of the Knockdown Building)

  • 이정윤;김홍
    • 한국안전학회지
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    • 제23권3호
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    • pp.30-35
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    • 2008
  • The recent fire incident in an elementary school of Chonan city causes the media focus on the fire safety of residential container buildings. In this study, real fire tests were conducted in this kind of buildings. Combustion products including $O_2$, $CO_2$, CO, $NO_x,$, $SO_x$, HCI, HCN were measured, in order to investigate the hazard-reduction effects of employing gas mask protected with filter during the fire emergency of residential container buildings. According to the test results, whether or not employing the filter showed a sheer difference in the toxicity of the fire-induced gases, and then the importance of wearing a gas mask was evidently demonstrated.

A Research on the Fire Safety for the Elderly Care Facilities in Japan

  • Kang, Shin-Wook;Ohnishi, Kazuyoshi
    • Architectural research
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    • 제14권3호
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    • pp.85-92
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    • 2012
  • In Japan, there are over the 100's fires in the social welfare organs every years. People are interested in fire protection who live in an institution for the aged or weak person's places and worried about it. I surveyed the social welfare organs were safety from fire to firewarden who worked at an institution for the aged in Tokyo. In the paper, I asked how do you think about the fire safety problems and condition of the facilities. And base on firewarden's view, I reviewed(examined) the fire prevention measures, each facility's problems and how to improve the fire protection.

Analysis of Fire Evacuation Behavior in a Primary School Environment

  • Lee, Chang-Seop;Kim, Hong;A. Kilpatrick;W. Fitzpatrick
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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    • pp.492-504
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    • 1997
  • The paper compares the statutory requirements for the design mid construction of primary schools in Korea and Scotland with respect to fire safety and examines the attitudes to, and the behavior in, evacuation scenarios of Primary school Pupils in both countries. The key behavioral issues examined are the effectiveness of fire safety training, the level of teacher dependency, the effect of spatial organization and gender differences both within and between Korea and Scotland.

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