• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.11
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• pp.1661-1670
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• 2016

In this paper, we present a risk prediction system and customized evacuation pathfinding algorithm in fire scenarios. For the risk prediction, we apply a multi-level clustering mechanism using collected temperature at sensor nodes throughout the network in order to predict the temperature at the time that users actually evacuate. Based on the predicted temperature and its reliability, we suggest an evacuation pathfinding algorithm that finds a suitable evacuation path from a user's current location to the safest exit. Simulation results based on FDS(Fire Dynamics Simulator) of NIST for a wireless sensor network consisting of 47 stationary nodes for 1436.41 seconds show that our proposed prediction system achieves a higher accuracy by a factor of 1.48. Particularly for nodes in the most reliable group, it improves the accuracy by a factor of up to 4.21. Also, the customized evacuation pathfinding based on our prediction algorithm performs closely with that of the ground-truth temperature in terms of the ratio of safe nodes on the selected path, while outperforming the shortest-path evacuation with a factor of up to 12% in terms of a safety measure.

• Journal of Korean Tunnelling and Underground Space Association
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• v.6 no.1
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• pp.51-59
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• 2004

The effectiveness of one dimensional critical velocity method for evacuation environment at 10MW fire size in a railroad tunnel have been investigated in this paper by three dimensional CFD method. It was performed to evaluate the evacuation environment in terms of temperature distribution, visible distance distribution and CO concentration at some tunnel inlet velocity, 1m/s, 2m/s (near critical velocity), and 3m/s. At all inlet velocity, passenger should give away downward the flow direction because the inlet velocity can not afford to sufficient evacuation environment for passengers. In case of 3m/s inlet velocity, however, the evacuation environment for passengers is better than the other cases. To provide more safe evacuation environment on fire situation, tunnel inlet velocity should be larger than critical velocity.

• Proceedings of the Korea Information Processing Society Conference
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• 2022.11a
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• pp.989-991
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• 2022

최근 들어 기후변화와 함께, 화재 발생이 증가함에 따라 인명피해와 경제적 피해가 늘고 있다. 화재 발생시 인명 피해를 줄여주는 소방시설 중 경보설비와 유도등설비는 위험 상황시 경보와 함께 동선을 유도하는 유도등을 보고 재실자들이 안전한 공간으로 신속하게 대피할 수 있도록 하는 소방설비 이다. 이중에서 유도등설비는 화재발생 상황에서 매우 중요한 역할을 맡고 있다. 특히 복잡한 동선을 가지고 있는 복합건물 및 지하철, 고층건축물에 신속한 대피 유도에 필요한 설비이다. 그러나, 화재 초기에 신속한 대피를 해야 하는데 5분도 되지 않아 화재로 인해 발생한 가스는 검은 연기로 유도등의 역할과 효과를 저해하는 현상을 가져온다. 즉 유도등의 녹색빛이 보이지 않는다. 이는 저시력자 또는 시력에 장애를 가지고 있는 자들은 더욱더 유도등을 확인하고 대피 하기란 쉽지 않게 된다. 이런 단점이 있는 기존의 유도등에 IoT(Internet of Things)와 함께 증강현실 이미지를 스마트기기에 활성화 한다면, 진한 검은연기로 인한 빛의 가림으로 인한 유도장애에 대해서 개선 할 수 있을 거라 생각되어, 변류기의 전류 감지를 시작으로 그 신호를 스마트기기에 녹색의 유도 이미지를 활성화하여 골든타임에 대피가 신속하도록 설비를 구현하여 그 가능성을 확인하였다.

• Fire Science and Engineering
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• v.22 no.5
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• pp.55-60
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• 2008

In this study, we conducted an FDS numerical simulation for the purpose of carrying out a basic assessment of the usefulness of the water spray for fire extinguishing. We analyzed the effect of securing the stability in temperature and smoke density in case of fire according to fire intensities (20MW, 50MW) and changes in wind speed. When there was no wind speed in tunnels, it was effective in securing the safety of people because the cooling effect of the water spray system had an excellent effect on reducing temperatures and smoke densities there. The higher a fire intensity is, the less effect it has on reducing smoke flows. When an air current exists in tunnels, its cooling effect disturbs the smoke stratification and lowers the visibility degree during evacuation. Therefore, the water spray for fire extinguishing should be put into action only after people take shelter during fire.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.3
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• pp.293-310
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• 2020

The purpose of this study is to present the most effective smoke exhaust mode by comparing the quantitatively evaluated risks according to the smoke exhaust mode when a train fire occurs in a subway platform. Therefore, applying the typical subway platform as a model, train fire scenarios are developed with the evacuation start time and location of the fire train for each exhaust mode. The fire accident rates (F) are calculated and the number of fatalities (N) was quantitatively estimated by fire analysis and evacuation analysis for each scenario. In addition, the F/N curve compared with the social risk assessment criteria and the following conclusions were obtained. In the event of a train fire at the subway station platform, the evacuation must start up within 600 s in maximum to ensure the evacuees' safety. To secure evacuation safety, it is advantageous to operate the HVAC system of the platform in the air-supply mode at station without TVF. Comparing the F/N curve for each exhaust mode with the social risk criteria, it turned out that the risk significantly exceeds the social risk criteria in case of no mechanical ventilation. As a result, this paper shows that the ventilation mode in which TVF are exhausted and HVAC system is operated in the pressurized mode are the most effective smoke exhaust mode for ensuring evacuation safety.

• Journal of the Korean Society for Railway
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• v.10 no.5
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• pp.511-519
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• 2007

This study provides comprehensive design improvements covering technical issues concerning life safety matter In case of fire train stoppage in the middle of a tunnel. Recently Government announced that most of subway platforms will have screen doors in 3 years. Therefore, many fire safety engineers considered that they may contribute on life safety on train stoppage in tunnel. Especially The screen door can protect platform from smoke along tunnel ceiling when fire train stopped in tunnel. The study showed that platform ventilation ducts and the a tunnel ventilation chimney in the middle of tunnel in exiting subway tunnel could not guarantee life safety ability in terms of RSET vs. ASET comparison. Furthermore during evacuation process many peoples may be threatened from the smoke spread from the origin of fire. Although only additional vertical route can be installed in tunnels In order to decrease RSET, it will costs high or no spaces remains in outside on the road. The study suggested that increase of ASET can be best solution without additional escape route, therefore alternative design methods suggested on the base of simulation results. Finally the study shows alternative methods can give good result in terms of evacuation performance evaluation. The evacuation performance evaluation helps the decision-maker to determine the preferred alternatives or upgrades to existing tunnel infrastructure and other measure to meet safety objectives. Finally, the study details the effectiveness of measures the can be taken to reduce the risk of incidents in subway tunnels.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.3
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• pp.257-266
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• 2015

This study introduce that we studied optimization and possibility of smoke spread prevention with air-curtain system in undersea tunnel named from Ho-Nam to Jeju line in domestic if a fire break out in train. To verify performance, air-curtain system is installed between rescue station platform and each door of passenger car to provide safety route to evacuator and we studied simulation model of various cases about 15 MW fire severity considering domestic specifications. As a result we verified the fact that CASE1(air jet with 15degree toward passenger car) and CASE 5 (air jet with 15degree toward passenger car and pressure air blast from cross passage) is best Smoke Spread Prevention and less inflow carbon monoxide. Through above results, we expect that air-curtain system is one of the facilities for fire safety and provide us safety platform route in undersea tunnel.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.3
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• pp.310-315
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• 2007

When a mail was given to users, each user's response could be different according to his or her preference. This paper presents a solution for this situation by constructing a u!;or preferred ontology for anti-spam systems. To define an ontology for describing user behaviors, we applied associative classification mining to study preference information of users and their responses to emails. Generated classification rules can be represented in a formal ontology language. A user preferred ontology can explain why mail is decided to be spam or non-spam in a meaningful way. We also suggest a nor rule optimization procedure inspired from logic synthesis to improve comprehensibility and exclude redundant rules.

• The Journal of the Convergence on Culture Technology
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• v.5 no.1
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• pp.249-255
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• 2019

Currently, most small theaters in Korea are not equipped with fire escape prevention laws unlike large theaters. The small theater is a place where many people stay in a small space, which can lead to a great deal of damage in the event of a fire. Therefore, we propose an efficient evacuation method using the evacuation behavior of the crowd as a way to minimize the casualties in case of a fire in a small theater.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.3
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• pp.215-226
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• 2015

In this study, with variables the cross section area ($97m^2$, $58m^2$, $38m^2$) and the wind velocity(0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5 m/s), the time of getting off train dependent on the way of itself and the width of the evacuation route was analyzed, and also fire and evacuation characteristics is reviewed by cross section area of each wind velocity. As the result, if cross section become smaller, the density of harmful gases in the tunnel increased more than the ratio of decreasing cross section area. In the case of small cross sectional area, the surrounding environment from initial fire is indicated to exceed the limit criteria suggested in performance based design. In the analysis of effective evacuation time for evacuation characteristics, the effective evacuation time was the shortest in the case of evaluating effective evacuation time by the visibility. Also, there was significant difference between the effective evacuation time on the basis of performance based evaluation and the effective evacuation time obtained by analyzing FED (Fractional effective dose), one of the analysis method obtaining the point that deaths occur, against harmful gases.