• Fire Science and Engineering
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• v.34 no.4
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• pp.13-21
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• 2020

This study tested the wood used in building interiors; each type had various incident heat fluxes based on their thickness. The combustion characteristics measured were effective heat of combustion, heat release rate peak and arrival time, maximum average rate of heat emission, and piloted ignition temperature. The wood specimens used in the experiment were 4.8 to 18 mm thick. 25, 35, 50, and 60 kW/㎡ were applied to the incident heat flux that the wood specimens were exposed to. The wood specimens tested were two types of medium-density fiberboard (each with a different density), treated red pine, particle board, and plywood. A comprehensive comparison of different fire characteristics was conducted to analyze the fire patterns corresponding to each type of wood in this way, the risk of fire was studied. The risk of fire was particularly high for particle board. The results of quantifying the fire characteristics of the types of wood studied could function as important input data with which to calculate the fire load of composite combustibles.

• Polymer(Korea)
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• v.25 no.1
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• pp.142-150
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• 2001

Until now rubber industry field has used organic solvent base adhesive, there was always existed a fire risk, variety of quality and harmfulness of human body. To solve this problem we were developed a new adhesive that was maked by raw materials of hydrocarbon series which has the properties of nonvolatile and high flash point. Because of this new adhesive has the properties of nonvolatile and non-harmfulness to the human body, we expected to solve the problems of a fire hazard and the pollution of the environmental. Instead of the rubber binder that is used to a present adhesive, the new idea is adopted in a new type of adhesive. Nonvolatile solvent penetrated to the rubber surface and caused the swelling in rubber surface and as a result of this action, it has the self-adhesive power. In comparision with the present adhesive a new type of adhesive remarkably improved the maintenance time of adhesion and the durability of this adhesive showed similar aspect. Because it did not exhibit a drop of physical properties of rubber which was caused by swelling effect, we estimate that new type adhesive are very stable and not reacted to several rubber additives. While present adhesive appear the crack at cutting surface of curing rubber that caused by gas, new type adhesive not exist these crack.

• Fire Science and Engineering
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• v.20 no.3 s.63
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• pp.29-34
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• 2006

The flash and fire point are the most important combustible properties used to determine the potential for the fire and explosion hazards of flammable material. The flash point is defined as the lowest temperature at which a flammable liquid gives off sufficient vapor to form an ignitable mixture with air near its surface or within a vessel. The fire point is the temperature of the flammable liquid at which there will be flaming combustion, sustained 5 seconds in response to the pilot flame. In this study, the flash points and fire points were measured to present raw data of the flammable risk assessment for acids, using Pensky-Martens Closed Cup(C.C.) apparatus (ASTM-D93) and Tag Open-cup (O.C.) apparatus(ASTM D 1310-86). The measured fire points were compared with the estimated values based on 1.11 times stoichiometric concentration. The values calculated by the proposed equation were in good agreement with measured values.

• Journal of the Korean Chemical Society
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• v.62 no.6
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• pp.433-440
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• 2018

The pyrolysis has been universally applied to recycle the waste artificial marble. However, the existing heat treatment equipment has relatively low heat transfer efficiency into the inner part of the waste artificial marble. Besides, it leads to unnecessary excessive gas during the partial carbonization of the polymethyl methacrylate (PMMA) and raises the risk of fire due to heat at an extremely high temperature. This study suggests the process of pyrolysis at the formation state after adding the starch to waste artificial marble to overcome above-mentioned problems. As the result of experiments, this method showed that the pyrolysis of waste artificial marble was greatly improved at comparatively low temperature condition of $350^{\circ}C$. Moreover, it also manifested the effect on securing the stability and energy savings necessary for the recovery of methyl methacrylate (MMA) and ${\alpha}$-alumina (${\alpha}-Al_2O_3$).

• Journal of the Korean GEO-environmental Society
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• v.21 no.5
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• pp.23-33
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• 2020

As the scale of the economy expands, the number of cases of damage in enclosed spaces such as tunnels is increasing due to the accident of transportation vehicles of dangerous substances such as explosive flammable materials that have increased rapidly. In the case of road tunnels in particular, in the aspect of protection against the long-winding trend and the environment in the downtown area, the number of cases of passing through the downtown area increases, and securing the safety of structures against unexpected extreme disasters such as explosions during tunnel passage is very urgent. For this reason, developed countries are already conducting a review of internal bombardment, but there are almost no evaluation and countermeasures for explosion risk in Korea. Therefore, in this study, in order to evaluate the explosion safety of road tunnels, a boiling liquid explosive explosion (BLEVE), which is considered to have the greatest explosion load among vehicles driving on the road, is set as a reference explosion source, and the equivalent TNT explosion load is used for simulation of the explosion. A method of conversion was presented. In addition, by applying the derived explosion load, dynamic behavior simulation was performed by assuming various variables for the tunnel, and the explosion safety of the tunnel was analyzed.

• Korean Journal of Optics and Photonics
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• v.29 no.3
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• pp.119-125
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• 2018

Hydrogen gas is an important and promising energy resource that has no emissions of pollutants during power generation. However, hydrogen gas is very dangerous because it is colorless, odorless, highly flammable, and explosive at low concentration. Conventional techniques for hydrogen gas detection are very difficult for measuring the hydrogen gas distribution at long distances, because they sample the gas to measure its concentration. Raman lidar is one of the techniques for remotely detecting hydrogen gas and measuring the range of the hydrogen gas distribution. A Raman lidar system with an on-axis optical receiver was developed to improve the range of hydrogen gas detection at long distance. To verify the accuracy and improvement in the range of detecting the hydrogen gas, experiments measuring the hydrogen gas concentration are carried out using the developed on-axis Raman lidar system and a gas chamber, to prevent explosion of the hydrogen gas. As a result, our developed on-axis Raman lidar system can measure a minimum hydrogen gas concentration of 0.66 volume percent at a distance of 50 m.