• Fire Science and Engineering
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• v.23 no.3
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• pp.73-78
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• 2009

The fire whirl occurring in the urban and/or wildland fire is generated by the instabilities of atmosphere. The fire whirl is a rare phenomenon, but highly destructive because it has high inhalation and lift force. In this study, experimental and numerical studies are performed with oriental oak leaves, for investigating of the fire whirl characteristics occurred in wildland fire. As a result of experiment, the circulation intensity increases as the induced air speed increases, then the heat release rate and flame height increase 22.8%, 18.4% compared with open fire in highest circulation. Furthermore the numerical results shows same trend with the experiment.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.2
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• pp.105-110
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• 2019

Most titanium alloy waste with cutting oil was discarded without recycling process so that it can be caused by metal and oil fires. However, there is no fire management system and studies on the titanium or titanium alloy waste in spite of high fire risk. The purpose of this experimental study is to identify the fire risk of the titanium alloy waste with cutting oil. We collected the 120g waste which was made in the biomedical titanium alloy cutting process. The waste was burned and conducted thermal image analysis with infrared camera. The experimental results which illustrated the process, characteristics, and trends of fire are presented. Firstly, the cutting oil was burned and partially the titanium alloy waste was burned. The maximum temperature of the fire was more than $650^{\circ}C$ in some specific spots. These results means when a lot of titanium alloy waste with cutting oil was ignited, this fire could connect the titanium fire. In other words, the fire has a flammable liquid fire and combustible metal fire at the same time. The experimental study could be used fire prevention, response, and investigation of the titanium alloy waste.

• Journal of the Korean Society of Safety
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• v.37 no.3
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• pp.16-23
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• 2022

This study aims to provide a fundamental material for identifying fire and no-fire signals using the detection signal characteristics of IoT-based fire-detection systems. Unlike analog automatic fire-detection equipment, IoT-based fire-detection systems employ wireless digital communication and are connected to a server. If a detection signal exceeds a threshold value, the measured values are saved to a server within seconds. This study was conducted with the detection data saved from seven fire accidents that took place in traditional markets from 2020 to 2021, in addition to 233 fire alarm data that have been saved in the K institute from 2016 to 2020. The saved values demonstrated variable and continuous VC-Signals. Additionally, we discovered that the detection signals of two fire accidents in the K institution had a VC-Signal. In the 233 fire alarms that took place over the span of 5 years, 31% of smoke alarms and 30% of temperature alarms demonstrated a VC-Signal. Therefore, if we selectively recognize VC-Signals as fire signals, we can reduce about 70% of false alarms.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.826-829
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• 2004

An increasing interest in fire safety engineering can currently be identified in Korea and overseas. The fire-resistant characteristics of spray coating material for fire protection with or without nano $Al(OH)_3$ colloid has been experimentally investigated and the results are presented in this paper. The fire-resistance characteristics of spray coating material with nano $Al(OH)_3$ were superior to those without $Al(OH)_3$. Especially, spray coating material with nano material showed that thermal characteristic in the early days was remarkably excellent.

• Journal of the Korean Society of Safety
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• v.29 no.1
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• pp.21-24
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• 2014

In this study, we have investigated the maximum smoke density and the initial stage smoke density in order to see the characteristics of smoke release of the architectural surface materials and the architectural adhesives, using smoke density chamber. As a result of the study, polyurethane foam showed the highest smoke density index, 206.55 within 10 min. In the case of the other samples, reinforced styrofoam was followed as 39.90, general styrofoam 33.73, and glass fiber 5.40, respectively. In the intial stage of a fire, it is forecasted actually to give hardship at the clear visibility. In the case of architectural adhesives, the highest ranking was those for windows and doors 509.64, stone 275.63, wood 232.25, tile 18.65, and styrofoam 6.44 were followed, respectively. This result is an early research to show characteristics of smoke release through experiment. However, it is meaningful that this study can be used as a basic for further study on architectural fire hazard prediction.

• 한국전산유체공학회:학술대회논문집
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• 2009.04a
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• pp.202-207
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• 2009

In this study, Numerical simulations were performed to analyze the characteristics of fire driven smoke flow for different location of fire source in the deeply underground subway station with using FDS code. The fire driven smoke-flow which was simulated by using Parallel Computational Method for fast calculation and LES for turbulence model. In this research, the fire location to obstruct a suitable egress from the fire disaster were discussed.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1570-1575
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• 2004

In order to evaluate the performance of fire-fighting agents used to protect structures from heat and fire damages, the thermal characteristics of fire-protection foams are experimentally investigated. The current research focuses on the destruction of a fire-fighting foam subjected to heat radiation. A simple repeatable test for fire-protection foams subjected to fire radiation is developed. This test involves foam generation equipment, a fire source for heat generation, repeatable test procedures, and data acquisition techniques. Results of the experimental procedure indicated that each thermocouple within the foam responded in a similar manner and gradually to a temperature of $15^{\circ}C{\sim}20^{\circ}C$. At this point, each trace generally rises to a temperature of approximately $90^{\circ}C$. The temperature gradient in the foam as time passes increases with increased foam expansion ratio. In addition, it is determined that the temperature gradient along the foam for depth decreases with increased foam expansion ratio.

• Journal of the Korean Society of Safety
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• v.24 no.4
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• pp.17-21
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• 2009

The fire whirl occurring in the urban and/or wildland fire is generated by the instabilities of atmosphere. The fire whirl is a rare phenomenon, but highly destructive because it has high inhalation and lift force. In this study, experimental study is performed with oriental oak leaves, for investigating of the fire whirl characteristics occurred in wildland fire. As a result of experiment, the circulation intensity increases as increasing of the induced air velocity, and then the fire whirl occurs. Also, the heat release rate and flame height increase 22% and 18% in highest circulation.

• Fire Science and Engineering
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• v.9 no.2
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• pp.10-16
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• 1995

This study discribes characteristics of water spray for extinguishment of gasoline fire. Experiments are carried out for the gasoline pool fire nth the atomizing nozzles. Droplet size, spray pressure, amount of water which reaches the flame base and velocity of water spray are measured to find extinguishment conditions. Air entrainment due to the water spray and extinguishing process of gasoline fire by water spray are visualized. Boundary conditions of water spray for extinguishment of gasoline pool fire is quantitatively shown. As the result of experiments, it is found that the velocity of entrainment air and sprayed water are almost same and the water droplets size having small diameter under 40$\mu\textrm{m}$ can not extinguish the fire because too small droplets does not reach the fuel surface.

• Fire Science and Engineering
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• v.22 no.3
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• pp.258-264
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• 2008

This study proposes the experimental methods which shows various guidelines for systematic study of surface forest fuels. The thermal characteristics of surface fire fuels such as Quercus Variabilis and Pinus Densiflora fallen leaves are measured using TGA and Oxygen Bomb Calorimeter. Both of them are common species of Korean forest. Also the combustion characteristics of surface fire fuels are analysed according to the methods which are commonly used in Pool Fire analysis. The measured parameters are gas velocity, temperature, flame height, heat release rate and mass loss rate. A system is designed to simulate the surface fire. Methods and results are shown for the application of forest fire study.