• 한국안전학회지
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• 제7권1호
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• pp.31-38
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• 1992

This paper presents a study on application of expert system technique for the diagnosis of fire-causes in plants. A need is recognized for new methods to diagnose exactly the causes of fires without the help of the human experts. To cope with the difficulty, the expert system techiuque is applied to this area. The expert system suggested in this paper is developed to infer the causes of fires(or, ignition source ) by using the information drawn from the circumstances in fire. For the convenience of inference, ignition sources we classified into eight types ; elecoic spark, adiabatic compression, welding spark, material of high temperature, impact and friction, spontaneous ignition, naked fire, and static electricity. The knowledge base is composed of the rule base and dynamic database, which contain the rules and facts obtained by the expenence in this area, respectively. Both depth-first search and backward chaining schemes are used in reasoning process. This expert system is written in an artificial intelligence language "PROLOG", and its availability is demonstrated through the case study.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.162-168
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• 1997

A theoretical model for the interaction of the moving heat source and a solid substrate when they are in contact is described. for purposes of the model the substrate is assumed to act as a continuum and the Fourier equation for transient. three-dimensional conduction is solved using Laplace and Fourier transformations. Unlike most previous models, this model shows the explicit relations between the properties of heat source and that of the substrate. Since the size, shape and speed of heat source impact the ignition of substrate, considerable attention is devoted to evaluating these parameters. Results are presented which show the effects of the size, shape and speed of heat source on the substrate.

• 한국안전학회지
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• 제36권3호
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• pp.1-6
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• 2021

Hydrogen is considered a cleaner energy source than fossil fuels. As a result, the use of hydrogen in daily life and economic industries is expected to increase. However, the use of hydrogen energy is currently limited because of safety issues. The rate of combustion of the hydrogen mixture is about seven times higher than that of hydrocarbon fuels. The hydrogen mixture is highly flammable and has a low minimum ignition energy. Therefore, it presents considerable risks for fire and explosions in all areas of hydrogen manufacturing, transportation, storage, and use. In this study, the auto-ignition characteristics of hydrogen were investigated numerically for diluted hydrogen mixtures. Auto-ignition temperature, a critical property predicting the fire and explosion risk in hydrogen combustion, was determined in well-stirred reactors. When N₂ and CO₂ were used to dilute the hydrogen/air mixture, the ignition delay time increased with increasing dilution ratios in both cases. The CO₂-diluted mixtures exhibited a longer ignition delay than the N₂-diluted mixtures. We also confirmed that lower initial ignition temperatures increased the ignition delay times at 950 K and above. Overall, the auto-ignition characteristics, such as the concentrations of participating species and ignition delay times, were primarily affected by the initial temperature of the mixture.

• 한국화재소방학회논문지
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• 제18권1호
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• pp.18-23
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• 2004

본 논문은 IEC형 불꽃점화 시험장치를 이용하여 저압 유도회로의 최소 점화한계를 프로판-공기 5.25 Vol.%의 혼합 가스에 대하여 실험적으로 구하였으며, 또한 유도회로의 인덕턴스 L에 안전소자로서 저항을 병렬접속 하였을 경우 프로판-공기 5.25 Vol.%의 혼합 가스에 대한 점화한계 개선효과를 고찰하였다. 그 결과, 최소 점화한계는 전류의 크기에 따라 좌우되었다. 또한, 전원으로부터 공급되는 에너지는 인덕턴스에 우선 축적되고, 그 초과분의 에너지가 폭발성 가스의 점화원으로 작용하였다. 점화한계 개선효과는 인덕턴스가 300mH일 때, 최고 330%의 개선효과가 나타났으며 인덕턴스가 클수록 점화한계 개선효과가 크게 나타났다. 또한 병렬로 접속한 저항의 크기가 적을수록 점화한계 개선 효과가 크다. 본 연구결과는 본질안전 방폭형 전기기기의 연구개발을 위한 기본자료로 활용할 수 있을 뿐만 아니라 이들 기기의 방폭 성능에 대한 시험자료로도 활용이 가능할 것으로 사료된다.

• 한국연소학회지
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• 제18권4호
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• pp.53-58
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• 2013

Lots of Coal power plants (about 30) using bituminous coals are being run in Korea. The use of high volatile low grade sub-bituminous coal is increasingly extended because of imbalance between the worldwide coal supply and demand. Mill-fire has been an important issue since the use of such sub-bituminous coal. In existing coal plants of Korea, shutdown of coal and air supplies could be only a way, and an alternative has not been found in suppressing the mill fire. The inside fowfield in the mills has a highly fuel-rich, low temperature, and high velocity and non-reactive such that it could be a nonreactive system essentially. Nevertheless, occasional fire-occurrence could be attributed to the existence of an ignition source. However it has not been so far investigated in detail. The current work has a focus on suppressing the mile fire via some parametric experimental study such as effects of temperature, residence time, ignition source, and inert gas mixing. The results show that an small amount of $CO_2$- or $N_2$-mixing with air is very effective in suppressing fire formation even at high temperatures or flying sparks. The results suggest that exhaust gas recirculation into the mill should be an alternative to suppress mill fire.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.124-132
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• 2010

To predict and analyze the rolling stock's fire growth is considered not only important factor in estimating hazard analysis of rolling stock, but also a primary factor in aspect of a rail load facility. Because it's could be regarded as a ignition source in risk assesment for the facility i.e. tunnel and station. However, currently, standardized method to predict and analyze the fire growth has not been completed yet. it is due to the fact that fire growth is not only depended on thermal property of interior materials, but also is affected dominantly by various factors such as ignition source (characterized by location, duration, and intensity), train running condition and in/exterior ventilation condition. Especially, ventilation condition is one of the most effective factor to affect fire growth in compartment space as noticed by under-ventilation fire condition. In this study, the effect of each ventilation condition on fire growth and load were examined through the numerical method through FDS (Fire Dynamics Simulator).

• 한국재난정보학회 논문집
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• 제16권2호
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• pp.383-391
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• 2020

연구목적 : 에너지 저장실의 외부 화염에 의한 내부자기 점화 및 점화를 식별하고, 과열로 인한 점화와 외부 열원에 의한 점화의 차이를 분석하는 것이다. 연구방법 : 분리막 녹는점 측정, 배터리 외부 수열 실험, 배터리 과충전 실험, 과충전과 외부수열에 의한 연소 시 전극 판 비교분석, 과충전 연소 특징, 외부수열 화재 연소특징, 3.4(전극판 비교)/ 3.5(과충전)/ 3.6(외부수열) 분석 실험을 하였다. 연구결과: 화재 발생 시까지 센서의 위치에 따른 온도 차이가 극심했음으로 기존처럼 한 모듈 당 온도 센서 두 개로는 측정값이 부족해 온도제어를 통한 화재를 사전에 방지할 수 없다고 판단한다. 결론: 단락이 점화원으로 작용하여 혼합가스에 착화돼 가스폭발이 발생하고, 폭발 압력에 의해 전극이 잘게 파손되며, 가루형태의 리튬산화물이 불꽃반응에 의해 폭죽과 유사한 불꽃이 분출되었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2149-2153
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• 2008

A large-scale fire test was done for interior materials from a vehicle installed within a fire test room. The interior materials are satisfied with the Korean guide for the safety of rail vehicle. The guide has taken effect since December 2004 in Korea. Ignition source (gas burner) was increased in several controlled steps. The objectives of this test are to assess the fire performance in terms of ignition and flame spread on interior lining materials and to provide data on an enclosure fires involving train interior materials that grow to flashover. This data will be used to develop and calibrate an Fire Dynamics Simulator (FDS) model for fire growth on the interior vehicle.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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• pp.227-243
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• 1997

Fire and smoke can from a small ignition source develop rapidly. Active systems in combination with Passive Fire Protection measures will offer highest safety standards to the building's developers and occupants. Nevertheless, the fire growth is very unpredictable and it is therefore essential at the planning stage that tested solutions are well selected according to National codes and later on installed by qualified contractors to ensure optimum performance. This demonstrates that Passive Fire Protection as safety measure cannot be neglected. Recent fire cases all over the world still proof that fire can develop any time and any where even in countries of high safety standards.

• 한국산학기술학회논문지
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• 제19권8호
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• pp.78-85
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• 2018

본 연구에서는 2017년 20건의 화재가 발생한 냉동창고 화재사례중 발화원인의 판정에 다수의 의견이 존재하였던 사례에 대해 연구하였다. 연구 방법론은 NFPA 921 CODE에서 규정하고 있는 과학적 화재조사 방법이다. 과학적 화재조사 방법은 가설설정을 통한 논리적 추론에 의한 화재조사 방법으로 발화원인 판단에 오류를 최소화 시킨다. 반면에 비과학적 화재조사 방법은 발화원인의 판단에 주관적 추측, 추론적 판단 등의 비합리적 요소의 개입으로 많은 오류를 발생시킨다. 이는 결국 인적, 물적 책임의 문제 및 학문적 퇴보를 가져온다. 특히 목격된 화재(Sighted fire)에 비해 목격되지 않는 화재(Fire not seen)의 경우 원인조사에 있어서 더 많은 발화원인 의 오류를 만든다. 본 연구에서는 2017년 **시 **마트에서 발생한 냉동창고 정온전선의 화재사례에 대해 화재조사 보고서의 검토, 현장조사를 바탕으로한 가설A 와 가설B의 설정하였다. 설정된 가설은 NFPA 921 code 규정하고 있는 연역적 검정 방법중 실험으로 검정하였다. 이러한 분석방법은 향후 목격되지 않는 화재(Fire not seen) 및 원인 불명 화재의 발화원인 판단에 NEW Paradigm의 구축 할 것이다. 또한 본 연구의 실험 자료는 냉동창고 제조사 및 운영사에 통보, 화재 예방을 위한 기초 자료로 활용 될 것이다.