• Journal of the Korean Institute of Gas
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• v.17 no.5
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• pp.75-80
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• 2013

In this study, the effect of phosphorus flame retardants on the flame retardancy of the rigid polyurethane foam(PUF) was studied. Tetramethylene bis(orthophos-phorylurea)[TBPU] and Tris(2-chloroethyl) phosphate[TCEP], Tris(2-chloropropyl)phosphate [TCPP], Triethyl phosphate[TEP] were used as flame retardant. It was found that TBPU added PUF exhibits low mean heat release rate(HRR), peak HRR, effective heat of combusion(EHC), mass loss rate (MLR), CO yield and $CO_2$ compared other flame retardants.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.4
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• pp.460-470
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• 1992

Thermogenesis in brown adipose tissue (BAT) can serve the animal in the regulation of its body temperature and of its body weight. Thermogenesis can be switched on by exposure of the animal to cold (non-shivering thermogenesis) or by overeating (diet-induced thermogenesis). BAT mitochondria are uniquely specialized for thermogenesis, possessing a specific proton conductance pathway that is regulated by the concentration of fatty acids in the cells of BAT. The level of fatty acids is in turn controlled by the lipolytic action of noradrenaline on the tissue. When the proton conductance pathway operates, the mitochondria are effectively uncoupled and exhibit extremely high rates of substrate oxidation with a great increase in heat production. Thus it is suggested that BAT is of importance in energy balance and human obesity treatment if thermogenesis can be stimulated specifically.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.5
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• pp.187-196
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• 1996

In this study, 3-dimensional finite element model of a diesel engine cylinder head was made to accomplish heat transfer analysis and also thermal stress and deformation analysis. Heat release analysis and Nusselt-Reynolds correlations were applied to determine the convective boundary conditions which are required for heat transfer analysis to calculate temperature distribution. Thermal stress distribution was also investigated from heat transfer analysis results. Steady state temperature and heat flux were measured by using K-type thermocouples and then compared with numerical results to give a guarantee for the propriety of numerical analyses.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.11a
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• pp.276-282
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• 1996

일체형원자로는 노심, 증기발생기, 가압기, 펌프 등 1차측 주기기들을 하나의 압력용기안에 모두 포함하고 있고, 또 1차측 냉각재가 원자로 안에서만 순환하므로 기존의 분리형원자로에 비해 구조특성상 대용량 원자로 냉각재 상실사고(LBLOCA)의 발생 가능성을 원천적으로 제거할 수 있다. 반면 원자로 냉각재의 보충 등을 위한 소형 배관의 파단 가능성은 역시 존재하므로 소용량 원자로 냉각재 상실 사고(SBLOCA)는 여전히 존재한다. 따라서 현재 한국원자력연구소에서 연구 개발중인 중소규모 전력생산 및 열 활용 목적의 일체형 원자로에는, 원자로 압력용기 외부에 별도의 압력용기(안전용기)를 설치하여 SBLOCA시 원자로 압력용기로부터 방출되는 냉각수를 안전 용기내에 보관하도록 함으로써 사고시 외부로의 방사성 물질 유출 가능성을 획기적으로 줄 일수 있는 설계 개념을 도입하고 있다. 본 논문에서는 안전용기의 설계시 효율적인 냉각방식에 대한 열유체 해석적 접근을 시도하였고, 예비개념설계된 일체형 열병합원자로의 설계상의 특징들 및 안전용기 설계시 앞으로의 연구방향 등도 간략히 소개하였다.

• Journal of the Korean Institute of Gas
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• v.13 no.3
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• pp.49-53
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• 2009

Relief systems can improve the process safety because it has the function for the prevention of overpressure. Flare stacks is necessary to avoid explosion, radiation, or toxicity by waste-gas emitted from relief system. Safe combustion is one of the important factors to improve safety and the quantity and velocity emitted is ruled in the API code 521. Due to the pressure of released gas and mass flow, a flame from flare stack is similar to jet fire. In this study, we have investigated the effect of flame form on complete combustion and heat emission. API code was similar to jet fire model in flame length, the flame had an effect on the ground.

• Fire Science and Engineering
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• v.24 no.5
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• pp.60-67
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• 2010

Fire model shall be verified and validated to reliably predict the consequences of fires within its limitations. Generally the verification and validation procedures are conducted by comparison with experimental test data. This study aims to evaluate predictive capabilities of FDS in the pool fire with two rooms and the sensitivity between input parameters such as heat release rate and ventilation rate and the output values like temperature, concentration, and heat flux. The predictive capabilities of FDS will be evaluated by comparing FDS simulation results with PRISME experimental data which result from the international fire test project. The sensitivity analysis will be conducted to decide which one of input parameters affects outcomes by comparison of FDS results with ${\pm}$ 10% changes of input parameter. From this study, the FDS predictive capabilities are within 20% error range. Heat release rate as input parameter affects most of outcomes and flow rate only has relation with concentration of oxygen and combustion products.

• Journal of the Korean Wood Science and Technology
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• v.43 no.1
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• pp.96-103
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• 2015

The aim of this paper is to analyze combustion characteristics of treated woods by fire retardants which are prepared by several borate and phosphate compound solutions. The combustion characteristics for flame retardant treated wood were carried out using thermogravimetric analysis (TGA) to measure their combustion heat and flame retardant test using cone-calorimeter. The result of TGA and flame retardant test showed that single chemical solution affected the char forming and flame delay. The mixed retardants solutions was believed to be related to the efficacy and property of single chemical. The retention value and concentration of the retardants also affected the performance of fire retardant treated woods. The fire retardants FR1 and FR2 satisfied the requirement of The 3 Grade of Korean building codes.

• Fire Science and Engineering
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• v.31 no.2
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• pp.37-43
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• 2017

The combustion characteristics of four kinds of wood specimens, such as Japan cedar, spruce, lauan, and red pine, were tested using the standards of Cone calorimeter (ISO 5660-1, 2) and smoke density tester (ASTM E 662). Japan cedar caught fire the quickest but the mean heat release rate was the lowest, $58.52kW/m^2$. The mean heat release rate of red pine appeared to be the highest, $71.75kW/m^2$. The lauan and Japan cedar generated relatively large amounts of carbon monoxide while the red pine and the spruce generated relatively large amounts of carbon dioxide. The red pine generated large amounts of smoke and the spruce generated the least amounts of smoke than the other samples. The total smoke release rate in the dynamic method was the highest in red pine and the lowest in spruce. The smoke density of red pine in the static method was highest in the non-flaming and flaming methods. In the non-flaming method, the smoke density of lauan was the second highest, whereas the flaming method was the least. In terms of the heat release rate, the fire risk from red pine was highest among the four test specimens. From the viewpoint of smoke generation, red pine was the most dangerous material in both dynamic and static methods.

• Fire Science and Engineering
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• v.34 no.1
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• pp.72-78
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• 2020

In this paper, the risk of damages to humans and properties due to fire explosions in gasoline storage tanks is identified, and the effects of radiant heat on adjacent tanks are evaluated to present the necessary area to secure safety. A simulation was conducted to evaluate the effect of radiant heat (Maximum emission) on adjacent tanks in an oil storage tank fire due to environmental conditions (Wind speed and temperature) in the Northern Gyeonggi Province. The result indicated that the radiant heat released in the fire of an oil storage tank was increased by approximately 1.9 times by the maximum wind speed and the difference occurred in the range of 700~800 kW by the maximum temperature. If a storage tank fire occurs, securing approximately 34.4 m of holding area is necessary. In the future, evaluating the radiant heat emitted by the fire of gasoline storage tanks will be required by applying various environmental conditions, and through this, research on specific and quantitative holding area is required.

• Journal of Energy Engineering
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• v.14 no.1
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• pp.1-10
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• 2005

The combustion reactivity of char depending on the pyrolysis pressure was investigated with Pressurized Thermogravimetric Analyser. The amounts of volatiles released at pyrolysis pressure of 1, 8 and 15 atm were, first, measured with Alaska, Adaro and Denisovsky coals. Reactivities of chars produced at var-ious pyrolysis pressure were evaluated at atmospheric pressure and 500℃, and analysed in terms of char crystal structure, surface area, pore characteristics and chemical composition of char. Finally, the combustion reactivities of three chars were examined at pressure of 1 atm, 8 atm and 15 atm. From this study, it was recognized that the amount of volatiles released decreases with increase in pyrolysis pressure, and reaction rate of char produced at higher pyrolysis pressure was lower than that at lower pyrolysis pressure. It might be resulted from the difference in char surface area and pore characteristics rather than char crystal structure and chemical characteristics. At 15 atm, kinetic parameters of Alaska char were obtained with the grain model, and these were 56.8 KJ/mole for activation energy and 222.34 (1/min) for frequency factor.