• Fire Science and Engineering
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• v.22 no.2
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• pp.121-128
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• 2008

Adverse health effects of inhaled smokes are associated with the amount of the particles deposited in human lung. Lung model is needed to simulate smoke deposition because of the hardness of the in vivo deposition experiment. However, it is hard to realize the successively decreasing bifurcations in the model. In this work, an experimental lung model was developed to simulate the smoke deposition in the lung. Instead of bifurcating airways, the lung model was made of packed beds of which size decreased downwards. The experimental results using this model showed good agreements with existing results for real lung in the deposition characteristics. The model could be applied to the studies of health risk assessment of the inhaled smoke particles generated by fire.

• Fire Science and Engineering
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• v.20 no.4 s.64
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• pp.1-12
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• 2006

In this study, CFD computer simulations by FDS are carried out in order to confirm the performance of the combined operation of both sprinkler system and smoke curtain of 0.54 m depth installed for cooling and blocking the smoke which propagates beneath the sloped ceiling of a stairway corridor of which dimensions are 17.92 m long, 4.00 m wide, and 6.12 m high. It is shown that the response time of sprinklers decreases with fire size and it increases more about 1.1 second in case without smoke curtain than in case with smoke curtain, that the time of smoke transport from the fire source to the stairway outlet decreases considerably with fire size, and that the delay effect of smoke transport is not related to the sprinkler system, whether it is operated or not. This study shows that the combined operation of both sprinkler system and smoke curtain is very effective in smoke cooling, but it is a little for effect on smoke blockage. Although the hazard of skin burn due to radiative heat flux from hot smoke layer is decreased by spray cooling effect, the hazard of smoke suffocation and the weakening of visibility is increased by smoke downdrag and the turbulence of smoke-air mixing due to water spray. These conditions may result in preventing occupants from going out of the stairway during evacuation.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2009.04a
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• pp.194-199
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• 2009

소방대상물에 기 설치되어 있는 연기감지기에 대한 정밀한 감지 성능 시험의 요구에 부응하기 위하여 현장에서 국내 기술기준에 적합하게 시험할 수 있는 휴대용 연기감도 시험기에 대하여 연구하였다. 휴대용 연기감도시험기는 점검 현장에서 간이로 감도시험을 할 수 있도록 연기원으로 동양 2호지를 사용하여 연기를 발생시키고, 농도를 제어하고 일정풍속 유지가 가능하여 현장에 설치된 연기감지기의 정밀한 시험이 가능하도록 하였다.

• Fire Science and Engineering
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• v.32 no.6
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• pp.15-21
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• 2018

This study examined the flow characteristics of fire smoke under pressurized air ventilation conditions by carrying out fire simulations on multi-compartment enclosure, including room, ancillary room and stair case. Fire simulations were conducted for the air-leakage test facility, which was constructed to measure the effective leakage area and aimed to improve the understandings of fire and smoke movement by analyzing the overall behaviors of fire smoke flow and pressure distributions of each compartment. The simulation results showed that the heat release rate of the fires was controlled sensitively by the amount of air supplied by the ventilation system. An analysis of the velocity distributions between the room and ancillary room showed that fire smoke could be leaked to the ancillary room through the upper layer of the door, even under pressurized air supply conditions. From these results, it was confirmed that the fire size and spatial characteristics should be considered for the design and application of a smoke control system by a pressurized air supply.

• Fire Science and Engineering
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• v.19 no.1 s.57
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• pp.87-92
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• 2005

In this paper, numerical simulation are conducted to predict the characteristics of the heat transfer and smoke flow and evacuation in the road tunnel. Fire source are used about 30 MW and the turbulent flow characteristics are considered by standard k-epsilon turbulent model. The effect of transient thermal behavior and disaster prevention can be used for designing the road tunnel.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.12
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• pp.947-954
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• 2017

In case of a fire in urban large structures such as super high-rise buildings, evacuation guidance must be provided to the occupants in order to minimize human deaths and injuries. Therefore, it is essential to provide emergency evacuation guidance when a major fire occurs. In order to effectively support evacuation guidance, it is important to identify major items such as fire location, occupant position, escape route, etc. Also, it is important to quickly identify evacuation areas where residents can safely evacuate from a fire. In this paper, we analyze the CCTV video and propose a method of measuring visibility of the evacuation zone from the smoke caused by the fire in order to determine the safety of evacuation area. To do this, we first extract the background video from the smoke video to measure the visibility of the specific area due to smoke. After generating an edge-extracted image for the extracted background video, the degree of visibility is measured by calculating the change in the edge strength due to smoke.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.5
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• pp.1-7
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• 2010

Since subway fire disaster at Daegu, Korea smoke control system and passengers evacuation distance has been focused to reform. Existing smoke control facilities need to expand volume of ventilation capacity however, the complicate subway station structure can hardly react dispersion of smokes from massive subway cabin fire. Smoke flow at platform level move upward thought vertical stairway and passengers evacuation goes with same direction. The victims of evacuees from subway station fire mainly due to exposure of heat radiation and smoke. The study demonstration the effect of downward evacuates stairway system by separating evacuation route to smoke movement pass way including saving times of evacuation.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.7-10
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• 2011

최근 국제우주정거장에서 화재안전에 관한 중요성의 인식으로 화재의 감지/소화의 메커니즘을 구체적으로 이해하기 위한 다양한 연구들이 시도되고 있다. 본 연구에서는 국제우주정거장에서 각종 실험과 연구를 진행하는 가압모듈을 대상으로 환기, 연기거동 및 감지에 관한 수치모델링을 수행하였다. 수치모델링은 NIST에서 개발된 FDS (Fire Dynamic Simulator)가 사용되었다. 국제우주정거장 내부는 마이크로중력환경으로 부력이 존재하지 않아 화재 발생 시 화염 및 연기거동은 지상에서의 현상들과 큰 차이를 보이게 된다. 따라서 현재 가압모듈에서 적용되고 있는 환기조건의 변화에 따른 연기거동 및 감지특성에 대한 연구는 향후 국내의 국제 우주정거장 실험 참여를 위한 기초적인 정보를 제공할 것으로 기대된다.

• Fire Science and Engineering
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• v.22 no.4
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• pp.61-64
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• 2008

This paper studied on the response characteristics depending on service life of ionization smoke detector. The experimental samples used ionization smoke detectors (360 EA) for over 5 years which were influenced by environment set up with fire objects. The experimental method performed operate and non-operate test according to 'Type Approval and Technical Regulation of Detector (KOFEIS 0301)', for estimate the response characteristics of ionization smoke detector depending on service life. The results showed that their response characteristics were rapidly decreasing when the longer their using period. Accordingly, it is desirable that ionization smoke detector has to be changed for early fire detection when passed their service life.

• Fire Science and Engineering
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• v.30 no.5
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• pp.87-92
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• 2016

Amid the growing number of high-rise complex buildings in Korea, efficient smoke prevention technology in a fire is required and as an alternative of a mechanical smoke control system in high-rise buildings, the use of a smoke control system using sandwich pressurization has been on the rise. In such a system, the appropriate pressure difference and the data for designing the air supply and exhaust flow rate are necessary to prevent the spread of smoke and offer a tenable evacuation environment. As part of such effort, this paper presents a field test process and result after testing a building where such a smoke control system using sandwich pressurization has been installed. A ventilation rate of 6 cycles per hour were applied to simulate the air exhaust flow rate on a fire floor and the air supply flow rate on the floors above and below the fire floor. As a result of the system operation, pressure difference of approximately 260 Pa between the 12th floor of a fire and the 13th floor was generated. The over pressure of the experiment has a serious effect on the evacuation or fire compartment so that it is necessary to examine the improvement.