• Fire Science and Engineering
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• v.24 no.4
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• pp.12-17
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• 2010

The purpose of this study is to determine how effectively waste tire recycled material mixed with flame retardant work in combating fire. As discovered in the previous study, waste tire mixed with cement mortar has more insulation capacity. However, this mortar is weak against fire. Therefore flame retardant, with a specific proportional mix, will be added to increase its fire prevention capacity. Tests will be made in accordance with ISO 5657 procedures for measuring fire ignition time, flame and shape variation of test pieces at the Building Material Test Institute. The test piece will be set up with horizontal levels having a constant radiation heat of $1{\sim}5W/cm^2$. Temperature transfers and increases from the surface into the interior. Combustible gases result due to pyrolysis, and regular contact is maintained between the fire source and the center of the test piece for assessment purposes. Ignition has not been occurred without adding retardant meaning that there is almost no possibility of ignition of waste tire particle. This fact can be considered as fire load to appreciate a volume of combustion materials. Flame is not occurred due to heat-absorbing effect by adding non-organic series retardant into waste tire particle. Conclusions have been summarized as follows; 1) Combustion of building material can be decreased by adding retardant to waste tire-mixing mortar. But compressive strength and insulation capacity of the material should be measured later. 2) Firing prevention and ignition are main points of building fire. Reasonable fire engineering assessment of interior material should be made for establishing effective disaster prevention system.

• Fire Science and Engineering
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• v.34 no.3
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• pp.76-84
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• 2020

Most outlet fires occur around plug pins and plug pin receivers. However, no research has been conducted on ignitions at power connection points. This study confirms the possibility of ignition after incomplete connection, using a stranded wire, to the power connection point of an outlet. The experiment was divided into basic and reproducing experiments. The basic experiment confirmed the possibility of ignition according to the number of wire strands connected to the power connection point, and it identified the characteristics of the residue after the fire. In the reproducing experiment, lamps, vacuum cleaners, and heaters were connected to an outlet to check if the ignition at the connection advanced into a fire. The fire advanced due to the heat and arc generated at the connection point, and partial losses were identified in the U-type holder and clip. Accordingly, the results demonstrate that a fire may occur when the stranded wire is incompletely connected to the outlet. Moreover, it was confirmed that the cause of a fire can be determined based on the characteristics of the residue.

• Korean Chemical Engineering Research
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• v.62 no.4
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• pp.327-334
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• 2024

The risks associated with coal dust explosion were investigated by analyzing various characteristics affecting the possibility of explosion. Samples were collected directly from two regions of the transfer process where the most explosions occurred in coal-fired power plants, and the composition ratio and average particle diameter that could affect the experiment were considered. As experimental items, explosion intensity, particle size and distribution, moisture content, dust concentration, minimum ignition energy, minimum ignition temperature, and oxygen concentration that affect the explosion were evaluated. As a result, the explosion intensity was found to have a maximum explosion pressure of 7.1 bar at a dust concentration of 500 g/m³ in sample A, and the maximum explosion pressure increase rate was 366 bar/s. In terms of dust particle diameter and particle size distribution, sample A had an average diameter of 35 ㎛ (D 50%), which was smaller than sample B. The moisture content was 5.7% in sample A, which was more than twice as high as 2.5% in sample B. The minimum explosion concentration was 400 g/m³ in sample A, which was lower than 2,000 g/m³ in sample B, so it had a risk. Since neither sample exploded at 1,000 mJ, it is judged that if the minimum energy is 500 mJ or higher, it can be regarded as dust with a low sensitivity to ignition compared to similar previous studies. The minimum ignition temperature was 532℃ in sample A and 634℃ in sample B, so sample A was more dangerous than sample B. The marginal oxygen concentration was 18.0% in both samples, so it is judged that there is a constant risk of explosion in the atmosphere.

• Applied Chemistry for Engineering
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• v.18 no.2
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• pp.194-198
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• 2007

Veneer plate was painted by the treatment with ammonium salts such as ammonium chloride (AMCR), ammonium sulfate (AMSF), monoammonium phosphate (MAPP), and diammonium phosphate (DAPP) at room temperature. The physical property and flammability of painted veneer plate were investigated. In order to evaluate flammability of the treated veneer with ammonium salts, heat release rate (HRR) of the veneer was measured by a cone calorimeter according to ISO 5660-1 standard. The flammability painted veneener plate with ammonium salts was reduced compared to virgin veneer plate. The flashover possibility of veneer plates treated with these ammonium salts was examined by R. V. Petrella's classification using time to ignition and peak heat release rate. The specific gravities of veneer plates treated with only ammonium sulfate were higher than that of virgin veneer plate. Also, the veneer plates treated with ammonium salts showed lower equilibrium moisture contents over virgin veneer.

• Journal of Korean Institute of Fire Investigation
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• v.4 no.1
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• pp.62-69
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• 2004

The purpose of this study on the sheath heater having high occurrence of fires in a small work place because of not having the safety device, was to find out the characteristics required in the field examination of the fires in the courses of investigation. The results of the experiments conducted and reviewed on the basis of the fire cases whose conditions of the ignition possibility were divided into A, E, C and D are as follows: When the sheath heater without safety device is left on the condition of the heat accumulation of which the temperature rapidly rise, and then ignite the inflammables of the surroundings. In such cases, it was characterized that the color change trace appeared even if no short trace was discovered in the power line.

• Journal of Power System Engineering
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• v.6 no.4
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• pp.30-35
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• 2002

This study represents the effects of the material of the air cleaner on the performance in a 4-stroke spark-ignition engine for motorcycles. This study is mainly focused on the possibility of the adopting the STS wire mesh air cleaner of a S.I engine. For investigating the possibility of that, the engine power, the fuel consumption and the exhaust gas analysis were carried out for the synthetic fiber air cleaner and the different size of 200 mesh, 250 mesh, 300 mesh of STS wire mash air cleaner. As the results of this study, the performance of STS wire air cleaner was similar to the fiber air cleaner at 9000 rpm but 300 mesh of STS air cleaner had a high engine power and torque at 9500 rpm. In the case of the synthetic fiber air cleaner the concentration of CO was low at 6500 rpm and in the case of the 300 mesh in STS wire mesh air cleaner the concentration of HC was lowest at all experimental regions.

• 한국정보통신설비학회:학술대회논문집
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• 2009.08a
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• pp.184-186
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• 2009

In past, transformer connection study was concentrated on efficiency improvement and life time broadening. But environmental side began to become important recently. In existing, quick transaction of mineral oil used to insulation oil of transformer is possibility to be difficult and causes environmental pollution in case of was outpoured and there is worry of fire occurrence. Accordingly, nonflammable performance becomes many interest in excellent vegetable oil because ignition point is high than mineral oil and environment friendly material. But, vegetable oil is cooling of transformer and insulation problem of insulating paper for cause of insulation oil special quality. Therefore, in this paper, special quality of vegetable oil that there are being a lot of mineral oil and the latest interest examined about problem and consideration item to be solved to analyzed comparison and applies vegetable oil to transformer for electric power.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.499-502
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• 2003

Increase energy costs have placed demands for improved combustion efficiency, high equipment availability, low maintenance and safe operation. Simultaneously low NOx modification, installed due to stricter environmental legislation, require very careful combustion management. We aimed at gaining the relationship between burner flame image and emissions such as NOx and unburned carbon in furnace by utilizing the image processing method. For the first step of development, its possibility test was undertaken with bench furnace. The test proceeded to the second step with pilot furnace, the system was observed to be effective for evaluating the combustion conditions. By using this technology, it is possible to perform continuous monitoring of the combustion conditions and instant detection of individual changes for each burner to prevent future loss of ignition.

• Journal of Environmental Health Sciences
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• v.5 no.1
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• pp.1-9
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• 1978

Biological safety, physico-chemical and microbiological experiments were carried out in order to study the possibility of radiation sterilization on medical products, such as polyethylene and polystyrene bottles, gauze sponges and surgical silk suture. Results are as follows: 1. Biological test on plastic samples as to acute systemic toxicity, eye irritation, skin irritation, pyrogen, haemolysis showed satisfactory results. But physico-chemically, the oxidizable matter, nonvolatile residues, residue on ignition seemed to be increased slightly in irradiated samples, though the experimental results were within the range of U.S.P. 19, N.F. and K.P. III. 2. After irradiation, both plastic and gauze sponges showed considerable decrease in pH. 3. Most medical products were sterilized by 1.5 Mard. For the sterilization of the suigical silk suture, 4.5 Mrad is required dul to its radiation resistant micro-organisms. 4. Biologically, total dose of 2.5 Mrad was safe enough to sterilize the medical products, and physico-chemically the results are acceptable according to U.S.P. 19 and K.P. III. However, better results may be expected when the quality of material and additives are improved.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2280-2283
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• 1999

Close to high power radio/radar transmitters, there is a possibility that electrical sparks may occur at discontinuities in metallic structures. If these structures are in an area where flammable mixtures are present, there is a danger that fire or explosion may happen by these sparks. Voltage may be induced on these metallic structures by the radio-frequency transmitter. In this case, a person who comes into contact with these structure may be undergone a severe electrical shock. In this paper, assessment of the these hazards was investigated through experimental and evaluation for actual tower cranes near AM radio transmitters.