• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2000.06a
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• pp.124-129
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• 2000

산업현장의 건물, 설비 등의 보온 및 단열을 위해 우레탄폼, 스치로폼 등 다양한 종류의 프라스틱류 단열재를 사용하고 있다. 이들은 착화 및 연소속도가 빠르고 연소시 유독가스를 다량 발생시켜 심각한 재산 및 인명피해를 초래하고 있다. 그러나, 이들 발포플라스틱들은 연소하기 쉬운 재료로서 급속한 화염전파, 높은 열방출율, 많은 양의 연기발생 등 화재의 위험성이 상대적으로 높다는 문제점을 안고 있다. (중략)

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2000.06a
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• pp.156-159
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• 2000

경량소재로 사용되는 polyurethane은 난연화 및 강도유지를 위해 난연제, 섬유 및 무기충진제 등을 첨가하거나 고밀도화하여 사용하며 발포시켜 경량화하여 성형된다. Polyurethane 발포체는 자동차 내장재, 건축 구조재, 건축 내외장재, 가구재, 포장재료, 신발, 의류 제품, 단열재 등 다양하게 사용되고 있다. 이러한 polyurethane 발포체는 제조 및 가공의 편리함에 비해 화재발생시 연기발생량이 많고 연소가 용이하여 화재를 전파하는 매개물의 역할을 하여 피해를 더욱 가중시키는 취약점을 가지고 있다. (중략)

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.633-639
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• 2005

We studied three dimension numerical analysis in the case that a train stops in tunnels by fire. And the 'Fluent 6.1' which is CFD(Computational Fluid Dynamics) program was used in this study. We compare the smog diffusion in single/double track ordinary railway tunnels with that in double track high speed railway tunnels in this study.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.3
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• pp.529-534
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• 2004

Millimeter waves are potentially useful for high resolution ranging and imaging in low optical visibility conditions such as fog and smoke. Also, They are used for wide band communications. However, it is necessary to develop a theoretical and experimental understanding of millimeter wave propagation to assess the performance of millimeter wave systems. The intensity fluctuations and mutual coherence function (MCF) describe atmospheric effects on the millimeter wave propagation. Using the quasi-optical method (QOM), an efficient and practical method was suggested to obtain the intensity distribution of the antenna focal plane from MCF which can be determined using meteorological data.

• Fire Science and Engineering
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• v.19 no.1 s.57
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• pp.80-86
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• 2005

In this study effects of the natural wind and the forced smoke ejection by operating the exhaust fan are studied numerically to examine the flow characteristics of the smoke and heat generated from a fire on the platform of an underground subway station. Three different situations, including 1) the case with no natural wind and no exhaust fan operation, 2) the case with natural wind but no exhaust fan operation and 3) the case with no natural wind but exhaust fan operation, are considered for the numerical analyses. The numerical results show that the natural wind causes a rapid spread of the fire along the tunnel resulting in rapid spread of the smoke and heat over the platform which affects the escape. The operation of the exhaust fan also results in the rapid spread of smoke and heat over the platform, but the time required for reaching the safe escaping height of the smoke layer with the exhaust fan operation is much longer than that without the exhaust fan operation. The numerical results also show that the required capacity of the exhaust fan becomes larger when the effect of the natural wind is included.

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.4
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• pp.577-588
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• 2017

There are many constraints, both economically and ethically that experimenting human evacuation behavior in situations such as fire. Therefore, the evacuation behavior is simulated based on the existing studies. In recent years, the foundation has been established as computer performance advances, models closer to reality can be studied. In this study, the evacuation time in the subway platform was analyzed from modeling human behavior and smoke propagation in a fire. The evacuation efficiency was also examined by dividing the shape of the subway station platform by the stair position and comparing the evacuation times for each platform. As a result, it was found that the side platform was longer than the island platform by 36.82% more time to evacuation. The shape of the stairs is most advantageous in terms of evacuation form side type platform was 210 seconds and island type platform was 186 seconds, when a fire occurs in the center of the platform. And most favorable in location of evacuation stairs were located at 2/5 point and 4/5 from depending on the step location.

• Tunnel and Underground Space
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• v.25 no.6
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• pp.568-576
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• 2015

In this study, scenarios based on the leakage of highly compressed air and fire occurrence turned out to be high risks in an operation stage of CAES facility were constructed and estimated. By combining Bernoulli equation with momentum equation, an expression to calculate an impact force of a jet flow of compressed air was derived. An impact force was found to be proportional to the square of diameter of fracture and the pressure of compressed air. Four types of fire scenarios were composed to evaluate an effects that seasonal change and location of fire source have on the spread behavior of smoke. Smoke from the fire ignited in the vicinity of CAES opening descended more quickly below the limit line of breathing than one from the fire occurred 10 m away from CAES opening, which is expected to occur due to a propagation of wave front of smoke. It was shown that a rate of smoke spread of the winter fire is faster than one of the summer fire and smoke from the winter fire spreads farther than one of the summer fire, which are dependent on the direction of air flow into access opening. Evacuation simulation indicated that the required safe evacuation time(RSET) of the summer and winter fires are 262, 670 s each.

• Fire Science and Engineering
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• v.23 no.3
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• pp.67-72
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• 2009

This paper is for response feature of fire detectors not only to analysis response feature of fire detector, but also to observe flame spread of inside-building and fire enlargement by using the row house which is supposed to be broken up. Many kinds of popular detectors such as heat type detector(differential type, fixed temperature type, Analogue type)and smoke type(light scattered type, Analogue type, single alarm type) were installed in the house in order to check for the change of temperature by installing of thermocouples. As a result, smoke detectors are better than heat detectors when it comes to making effective fire-detect system in the row house.

• Journal of Korean Tunnelling and Underground Space Association
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• v.7 no.1
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• pp.27-36
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• 2005

The objective of this study was to analyze the smoke movement and to investigate the effect of exhaust ventilation using by shafts for case of fire in long tunnels. Based on Froude modeling, the 1/50 scaled model tunnel (20 m long) was constructed by acrylic tubes and test were carried out systematically. The results of the shaft height test show that the effect on exhaust ventilation by a shaft delays the propagation time of backlayering, and the temperature decreases as the shaft height increases. If the fire occurs downstream of the shaft, the backlayering develops to get stronger by the shaft exhaust effect and then the propagation of CO and temperature increase along with propagation of CO. That is to say, in the case of fire downstream of the shaft, the shaft has the advantage of smoke exhaust effects, but it might result in a dangerous situation for the escaping passengers due to the more developed backlayering.

• Fire Science and Engineering
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• v.17 no.4
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• pp.36-41
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• 2003

This experimental study shows the combustion characteristics for each coating thickness of water and oil paint which are used as fire retardant paints that prevent fire propagation through cables in underground culverts and trays. To evaluate combustion characteristics, smoke density(ASTM E 662) and Limited Oxygen Index(ASTM D 2863) experiment method was used. As the results of this study, the combustion characteristics of fire retardant paints produced the following : (a) The molt suitable coating thickness of fire retardant paint was 1.5∼2.0 mm in water paint and 0.2 mm in oil paint. (b) Flaming method in experiments of smoke density were found to be higher than Non-flaming method. (c) Water paint has the fire retardant effect and characteristics better than oil paint in measurement results of smoke density and oxygen index. (d) The oxygen index of water and oil fire retardant was able to know that it was satisfied a standard (30 or above).