• Structural Engineering and Mechanics
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• v.42 no.6
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• pp.815-829
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• 2012

This paper proposes a nonlinear computational modeling approach for the behaviors of structural systems subjected to fire. The proposed modeling approach consists of fire dynamics analysis, nonlinear transient-heat transfer analysis for predicting thermal distributions, and thermomechanical analysis for structural behaviors. For concretes, transient heat formulations are written considering temperature dependent heat conduction and specific heat capacity and included within the thermomechanical analyses. Also, temperature dependent stress-strain behaviors including compression hardening and tension softening effects are implemented within the analyses. The proposed modeling technique for transient heat and thermomechanical analyses is first validated with experimental data of reinforced concrete (RC) beams subjected to high temperatures, and then applied to a bridge model. The bridge model is generated to simulate the fire incident occurred by a gas truck on April 29, 2007 in Oakland California, USA. From the simulation, not only temperature distributions and deformations of the bridge can be found, but critical locations and time frame where collapse occurs can be predicted. The analytical results from the simulation are qualitatively compared with the real incident and show good agreements.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.206-212
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• 2009

Chemical behaviors of each surface material for interior facilities affect to fire initiation and growth in general fire situation. These chemical behaviors were characterized by thermal properties (Heat release rate, Pyrolysis rate, specific heat, etc) which could be derived from experimental test. Especially, Heat release rate which indicates aspect of fire size is one of the most important property to asses fire hazard and protection needs. The cone calorimeter test (ISO 5660) has recently assumed to a dominant role in bench scale fire testing to obtain the Heat release rate of materials. This value could be calculated by the 'Oxygen Consumption Method' under various producing irradiances to each surface of materials. In this study, Process of the cone calorimeter test was simulated by Pyrolysis model of FDS (Fire Dynamics Simulator by NIST) base on the ISO 5660 international standard. Then, we could estimate the simulation method of FDS in case of single materials through the comparative study with test results.

• Fire Protection Technology
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• s.19
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• pp.22-28
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• 1995

The rate of heat release is probably the single most important measure of fire hazard. Several tech-niques were developed for the measurement of rate of heat release, but were not suitable for fire test-ing purpose. Recently the application of oxygen consumption principle made it possible to development of well-characterized heat release rate measurement apparatus, the furniture calorimeter for large-scale fire tests and the cone calorimeter for bench-scale fire tests. The cone calorimeter can be used to determine the ignitability as well as heat release rate and smoke development, mass loss rate, combustion gas production etc. from burning materials. Thus, test method using cone calorimeter, an internationally recognized and accepted for the evalua-tion of fire properties, is a very promising tool for combustion study on various kind of materials and products.

• Fire Science and Engineering
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• v.28 no.2
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• pp.26-33
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• 2014

Recently in Korea, the interest for using window and window-wall in building picks up due to the beauty and utilization of space. But, interior space of the buildings shall be compartmentalized by fire resistance structures in accordance with the Korean building codes to prevent the spread of flame and damage of human life in fire. In case of installing non-insulated glazed window in compartment wall, the flame spread to adjacent space and the damage of human life by radiant heat can occur in fire. On this study, to confirm the risk of radiant heat for non-insulated glazed window in fire, the fire resistance tests were conducted. The temperature rise and heat flux on unexposed space was measured and analyzed.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.6
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• pp.1368-1373
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• 2008

This study was done to calculate the specific indicators of Fire-Heat Pattern Identification and Yin Deficiency Pattern Identification settled by tentative Korean Standard Differentiation of the Symptoms and Signs for Stroke. The subjects were 764 hospitalized patients with stroke, and a list of registry was made for each of them. Frequency and Correlations among Fire-Heat and Yin Deficiency indicators were studied. Fire-Heat pattern group included 175 patients out of 764, Yin Deficiency pattern group included 103 patients out of 764. Among the indicators of Fire-Heat pattern, those, in order of highest frequency, were 'heat vexation and aversion to heat', 'reddened complexion', 'thirst'. Among the indicators of Yin Deficiency pattern, those, in order of highest frequency, were 'dry mouth', 'red tongue', 'fine and rapid pulse'. Among the Fire-Heat pattern indicators, 'yellow fur' and 'thirst', 'heat vexation in the chest' and 'vexation and insomnia' showed most significant correlation. Among the Yin Deficiency pattern indicators, 'aphtha or tongue sore' and 'heat in the palms and soles', 'red tongue' and 'dry fur' showed most significant correlation. 'Reddened complexion', 'dry eyes', 'surging and parid pulse', 'heat vexation and aversion to heat' are classify between Fire-Heat pattern and Yin Deficiency pattern. 'Surging and parid pulse', 'Reddened complexion' are mostly representative of Fire-Heat pattern and 'fine and rapid pulse' are mostly representative of Yin Deficiency pattern.

• Fire Science and Engineering
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• v.21 no.3
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• pp.61-68
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• 2007

The purpose of this study analyzes heat flows and fire behavior through a reduced-scale model experiments about change of wind velocity in underground life space. When the wind velocity is increased the temperature rise time of the fire room was risen fast. And temperature of fire room was increased. And increase of wind velocity displayed maximum temperature at an opening of the fire room. Heat flows by fire spread increase size of smoke occurrence and flame, and displayed high temperature distribution in passageway than inside of neighborhood department promoting eddy flow spread as wind velocity increases. Finally, heat flows are decided by wind and wind velocity at fire of underground life space, and Wind velocity increases, temperature increase and decrease could confirm that is gone fast.

• Fire Science and Engineering
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• v.32 no.4
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• pp.1-6
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• 2018

As a preliminary study to quantify the measurement uncertainty of the Schmidt-Boelter type heat flux gauge, the present study has been conducted to evaluate the measurement error due to the calibration constant supported by manufacturer. Calibrations of heat flux gauges are performed at NIST Fire Research Division using a calibration facility with heat source of a 2000 W halogen-tungsten filament lamp and the calibration constant is obtained by comparing the response of the reference and a standard heat flux gauge at the same irradiance conditions. Calibration for heat flux gauges made by three different manufacturers is compared with their factory calibration constant. Relative error due to fluctuation of output signal from heat flux gauges does not exceed 1% of the mean value and the relative error between calibration of this study and factory calibration constant ranged from 1.5% to 14.3%. The present study shows that a continuous and periodic calibration is necessary for accurate heat flux measurement.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.126-131
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• 2008

Fire-fighters have been struggling against heat and dense smoke caused by fire when it occurs especially at the basement or the inner place of a building. An indoor fire-fighting robot with well heat-resistance, great searching cameras and good extinguishing ability has been recently developed. It never suffocate, coming into the fire district and extinguishes fire directly. In this study, several experiment was conducted to promote field working ability of the fire-fighting robot. As a result, heat resistance, water discharge and field working appeared satisfactory.

• The Journal of Internal Korean Medicine
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• v.30 no.4
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• pp.772-779
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• 2009

Object : In the present study, we investigated the obesity and blood parameters between Qi-deficiency and Fire/Heat pattern identification/syndrome differentiation (PI/SD) in acute stroke patients. Materials and Methods : A total of 391 stroke patients within 7 days after onset were consecutively recruited from 12 hospitals across South Korea from Nov. 1st, 2006 to Jun. 31st, 2009. They were diagnosed as Fire/Heat or Qi-deficiency among five PI/SD subtypes by two independent stroke experts. We investigated the differences of obesity and blood characteristics between Fire/Heat and Qi-deficiency by statistical analyses. Results : In male subjects, obesity was significantly associated with Fire/Heat PI/SD. The averaged mean BMI ($24.13kg/m^2$) and waist circumference(89.34cm) of the Fire/Heat group were higher than those of the Qi-deficiency group ($22.60kg/m^2$ and 83.43 cm, respectively). The number of obese patients was larger in the Fire/Heat group than in the Qi-deficiency group (p = 0.001). Hyperlipidemia was also related with Fire/Heat. However, obesity was not associated with PI/SD in female subjects where the number of hyperlipidemic patients was higher in the Qi-deficiency group. Among blood parameters, the levels of triglycerides and fasting blood sugar were higher in the Fire/Heat group compared with the Qi-deficiency group in male subjects. However, total cholesterol of the Qi-deficiency group was higher than in the Fire/Heat group among female subjects. Conclusion : This study shows that obesity and hyperlipidemia are significantly difference between Qi-deficiency and Fire/Heat. We suggests that PI/SD may be associated with clinical characteristics and large population study between PI/SD and clinical characteristics including blood parameters are needed.

• Fire Science and Engineering
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• v.32 no.6
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• pp.28-33
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• 2018

To measure the full scale fire test and heat release rate of bed mattresses according to the building compartment space, a fire test was performed using the Standard test method to determine the heat release rate of mattresses and mattress sets (KS F ISO 12949: 2011). Both test locations showed similar fire growth until approximately 3 minutes after burner ignition. After 3 minutes, the heat release rate in the test room was higher than the open calorimeter. For bed mattresses (SS), the maximum heat release rate in the open calorimeter was 735 kW and the maximum heat release rate in the test room was 992 kW. For bed mattresses (Q), the heat release rate in the test room increased more rapidly than the open calorimeter. The maximum heat release rate in the open calorimeter was 1,087 kW (346 s) and the maximum heat release rate in the test room was 2,127 kW (287 s). The difference between the maximum heat release rate and the measurement time according to the test location was confirmed.