• Journal of Korean Association for Spatial Structures
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• v.10 no.4
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• pp.85-92
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• 2010

Use of concrete has undoubtedly become widespread in construction and civil engineering. Sensors are used to add functional characteristics to concrete. Self-diagnosis concrete is also being developed. The thermal protector used in the study is a sensor using the linear expansion and cubical expansion of metal. The LED(Light Emitting Diode) is a phototransistor type, and to secure high-sensitivity light, the prices of these sensors are low. Rising temperatures of concrete elements can be predicted from LED of the external virtual beam due to operation of thermal protector sensors of concrete beam caused by fire load on the concrete specimen. In this study, the development of fire-diagnosis concrete using composite sensors are the fundamental study for damage detection using simply measurements.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.349-356
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• 2020

The heat release rate (HRR) and fire growth rate of fire for the solid combustibles consisting of multi-materials was measured through the ISO 9705 room corner test, and the computational analysis in a closed compartment was performed to simulate a fire using the heat release rate prediction model provided by a Fire Dynamics Simulator (FDS). The method of predicting the heat release rate provided by the FDS was divided into a simple model and a pyrolysis model. Each model was applied and computational analysis was performed under the same conditions. As the solid combustible consisting of multi-materials, a cinema chair composed mostly of PU foam, PP, and steel was selected. The simple model was over-predicted compared to the predicted heat release rate and fire growth rate using the pyrolysis model in a closed compartment.

• Smart Media Journal
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• v.13 no.6
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• pp.54-61
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• 2024

Recently, due to the increase in domestic and international online e-commerce platforms and the increase in container traffic at domestic ports, the operating ratio of large trucks has increased, and the number of truck fires is continuously increasing. In particular, spontaneous combustion is the most common cause of truck fires. Various academic approaches have been attempted to prevent truck fires, but due to the lack of research on the spontaneous tire ignition phenomenon that occurs during braking, this research directly designed and manufactured an experimental device to establish an environment similar to the braking system of a truck. A non-contact temperature sensor was installed on the brake device of the experimental device to collect temperature data generated from the brake device. Based on the data collected from the temperature sensor of the brake device and the temperature sensor on the tire surface, the ARIMA model among the time series prediction models was used to Appropriate parameters were selected to suit the temperature change trend, and as a result of comparing and analyzing the measured and predicted data, an accuracy of over 90% was obtained. Based on this, a plan was proposed to reduce the rate of fires in trucks by providing real-time warnings and support for truck drivers to respond to overheating phenomena occurring in the braking system.

• 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.

• Fire Science and Engineering
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• v.18 no.2
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• pp.1-6
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• 2004

In this study, numerical simulations were conducted to analyze an effect of the aspect ratio on smoke movement in tunnel fires using FDS 3.0. It was confirmed an application for tunnel fires in comparison with experimental results. The results showed relatively good agreement with experimental data within 1$0^{\circ}C$. Clear height of CFD by velocity distribution was about 3% higher than that of experiment. Smoke movement was confirmed by the analysis of temperature and velocity field. Results from variation of the aspect ratio showed good agreement with experimental data. The temperature at the vicinity of the fire source became lowly with the increase of the aspect ratio. But, decrease rate of the temperature was reduced by the decrease of the heat loss to the width direction.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2000.06a
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• pp.144-149
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• 2000

최근에 국내에서도 대형 쇼핑 몰이나 건축물에 부속된 아트리움 등 대형공간을 도입한 건축물이 점차 증가하고 있다. 따라서 건물 방화 설계자는 화재시 공간의 특성에 따른 열과 연기의 확산과 이동에 관한 정량적인 해석이 필요하지만 국내에서는 아직 이에 대한 관련 규정이 미비한 실정이다. 대형 공간의 공학적인 해석은 크게 실험을 통하여 제시되는 계산공식을 이용하거나 대상 공간의 화재 조건을 예측하는 컴퓨터 모델을 이용할 수 있다. 외국의 경우, 미국의 NFPA 92B는 이러한 공간에 대한 제연 시스템에 적용하는 공식과 계산식을 제시하고 있으며 이를 통하여 연기나 열 감지기의 작동시간, 연기 발생비율, 연기 층의 하강을 제어하기 위한 배기량 등을 계산할 수 있다. (중략)

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2013.04a
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• pp.41-41
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• 2013

화학산업이 발달함에 따라 화학 산업 현장에서 사용되고 있는 가연성물질들의 여러 가지 화재 및 폭발 위험이 증가되고 있으며, 화재 및 폭발의 예방 안전을 위한 화학공정설계 및 대처에 있어, 물질의 연소특성치 데이터를 필요로 한다. 인화점은 가연성 액체를 다루는 공정에서 안전한 취급과 사고방지를 위해 중요한 자료가 되며, 화재의 위험을 나타내는 지표로서 가연성액체의 액면 가까이서 인화할 때 필요한 증기를 발산하는 액체의 최저온도, 그리고 가연성증기의 포화증기압이 공기와 혼합기체의 폭발한계 하한농도와 같게 되는 온도로 정의한다. 본 연구에서는 2성분계 혼합물에 대해 인화점을 측정하였고, 측정값을 Raoult의 법칙과 다중회귀분석(Multiple Regression)을 도입하여 이론값과 비교 하였다. 따라서 본 연구에서 제시된 방법론에 의해 아직까지 밝혀지지 않은 순수가연성액체와 가연성혼합물의 인화점을 예측하는 방법을 전개하고자 하며, 실험에서 찾고자하는 자료에 도움을 주고자 한다. 본 연구를 바탕으로 혼합물의 인화점 예측 방법과 실험에서 측정한 자료를 화재 및 폭발을 방지하는 기초 자료로 제공하고자하며, 산업현장에서 취급되고 있고 위험성 평가가 되지 않은 보다 많은 물질에 대한 이론 및 실험 연구에 활용 되도록 하는데 그 목적이 있다.

• Fire Science and Engineering
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• v.22 no.4
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• pp.85-94
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• 2008

The purpose of this study is to obtain the fundamental fire resistance performance of engineered cementitious composites (ECC) under fire temperature in order to use the fire protection material in high-strength concrete structures. The present study conducted the experiment to simulate fire temperature by employing of ECC and investigated experimentally the explosion and cracks in heated surface of these ECC. In the experimental studies, 5 HSC specimens are being exposed to fire, in order to exami ne the influence of vari ous parameters (such as depth of layer=20, 30, 40 mm; construction method=lining and repairing type) on the fire performance of HSC structures. Employed temperature curve were ISO 834 criterion (3 hr), which are severe in various criterion of fire temperature in building structures. The numerical regressive analysis and proposed equation to calculate ambient temperature distribution is carried out and verified against the experimental data. By the use of proposed equation, the HSC members subjected to fire loads were designed and discussed.

• Journal of the Korean Institute of Gas
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• v.10 no.2 s.31
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• pp.7-13
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• 2006

In order to evaluate the fire and explosion involved and to ensure the safe and optimized operation of chemical processes, it is necessary to know combustion characteristics. The explosion limit, the heat of combustion, flame temperature and temperature dependence of the lower explosive limit are the major combustion characteristics used to determine the fire and explosion hazards of the flammable substances. The aim of this study is to investigate interrelationship of explosion characteristics and the temperature dependence of the lower explosion limit at elevated temperature for akylketones. By using the reference data, the empirical equations which describe the interrelationships of explosion properties of akylketones have been derived. Also, the new equations using the mathematical and statistical methods for predicting the temperature dependence of lower explosion limits of akylketones on the basis of the literature data are proposed. The values calculated by the proposed equations agreed with literature data within a few percent. From the given results, using the proposed methodology, it is possible to predict the explosion limits of the other flammable substances.

• Fire Science and Engineering
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• v.18 no.1
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• pp.1-6
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• 2004

In the reutilization process using limonene, the organic solvent to reduce volume of EPS, the AIT was measured with the variation of concentration and volume of mixture, in order to present the fund-mental data on the fire hazard assessment of limonene - EPS mixture at storage and handling. And ignition zone was compared with non-ignition zone. The equation related to AIT, activation energy and ignition delay time, used by the most scientific basis for predicting AIT values, was suggested using linear regression analysis as ln t = 0.704/T-5.819. And the equation related to concentration of mixture and AIT was also suggested to predict ignition hazard of combustible mixture using nonlinear regression analysis as $T_m/=248.32+69.27X+172.60X^2$. It enabled to predict ignition temperature according to variation of ignition delay time and concentration of mixture by the suggested equations.