• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.154-161
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• 1997

Several studies have developed upward flame spread models which use somewhat different features. However, the models have not considered the transient effects of the igniter and the burning rate. Thus, the objective of this study is to examine a generalized upward flame spread model which includes these effects. We shall compare the results with results from simpler models used in the past in order to examine the importance of the simplifying assumptions. We compare these results using PMMA, and we also include experimental results for comparison. The results of the comparison indicate that flame velocity depends on the thermal properties of a material, the specific model for flame length and transient burning rate, as well as other variables including the heat flux by igniter and flame itself. The results from the generalized upward flame spread model can provide a prediction of flame velocity, flame and pyrolysis height, burnout time and position, and rate of energy output as a function of time.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.04c
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• pp.1-5
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• 2008

In this paper, we proposed that when combustible burn with ultraviolet radiation, introduce fire detector with sensor of private-use detectable light energy as ultraviolet in energy of electromagnetic-wave type radiate from flame. This research using ultraviolet flame sensor is pyro-electric ultraviolet sensor based black body radiation theory. To have high sensibility and to gain proper output voltage, it has high responsive performance. This research introduced UV flame detector and proposed method of false alarm reduced to resemble fire. the result proposed the prevention and extinction of fire technique degree, certificated operation of detector.

• Fire Science and Engineering
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• v.24 no.3
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• pp.72-77
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• 2010

Honeycomb core structure with its excellent stiffness and strength is being utilized in many fields such as interior building material. Because it is inexpensive and renewable, honeycomb paper production is economically and environmentally helpful. However, the paper needs to be fireproofed because it is vulnerable to fire. In this study, we have undergone the performance evaluation process of the honeycomb paper which is widely used as interior material of a fire door and packing material. Four kinds of honeycomb (a honeycomb made of flame-resistant paper; a honeycomb attached with conventional flame-resistant film made in the laboratory; honeycomb impregnated with flame retardant; a honeycomb attached with flame-resistant film after impregnating fire retardant) were used in the study to compare the fire retardant performance. As a result, the honeycomb with impregnated flame retardant showed the highest performance. The flame-resistant film was effective in delaying the igniting time but had a negative effect on the rate of heat and smoke production.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.184-188
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• 2008

This study was carried out to investigate the flame retardant characteristics of wood finished with painting by followed in exposure conditions and flame retardant application method. According to painting types and flame retardant application methods salting occurrences undergoing an influence about the wood finished painting, confirmed. And influence to flame retardant characteristics of exposure condition on large scale not to be and occurrence quantity of the combustion gas undergone and influence In application method of flame trtardant.

• Fire Science and Engineering
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• v.23 no.5
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• pp.78-83
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• 2009

17 kinds of fire resistant paint which are currently used were painted on the MDF, to find flame resistance performance and smoking characteristics according to principal ingredient and characteristics of fire resistant paint. 45 degree combustion test and smoke density test were conducted to investigate the flame resistance performance and smoking characteristics. According to the 45 degree combustion test, acrylic resin type fire resistant paint showed the most excellent fire resistance performance. And the water soluble fire resistant paint showed better fire resistance performance compare to the solvent soluble paints. Also gloss paint showed better fire resistance performance than the flat paint. Based on the smoke density test, the smoke generation of fire resistant treated specimen of acrylic resin type was least. And the water soluble fire resistant paint generate little smoke than solvent soluble fire resistant paint.

• Journal of the Korean Society of Combustion
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• v.17 no.4
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• pp.21-29
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• 2012

Due to a significant leap in the science and technology, the manned space exploration that has started with suborbital flights is now being expanded into the deep space. The space superpowers such as the U.S. and Russia have been making an effort to further develop the manned space technology. Among such technologies, the fire safety technology in microgravity has recolonized as one of the most critical factors that must be considered for the manned space mission design since the realistic fire broke out onboard the Mir station in 1997. In the present study, the flame characteristics such as flame ignition, shape, spread, and extinction that are critical to understand the fire behavior under microgravity conditions are described and discussed. The absence of buoyancy in microgravity dominates the mass transport driven by diffusiophoretic and thermophorectic fluxes (that are negligible in normal gravity) and influences the overall flame characteristics-flame ignition, shape, spread, and extinction. In addition, the cabin environments of the pressurized module (PM) including the oxygen concentration, ambient pressure, and ventilation flow(which are always coupled with microgravity condition during the ISS operation) are found to be the most important aspects in characterizing the fire behavior in microgravity.

• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.4
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• pp.516-521
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• 2010

In this paper, we propose a video-based intelligent unmanned fire surveillance system using fuzzy color models. In general, to detect heat or smoke, a separate device is required for a fire surveillance system, this system, however, can be implemented by using widely used CCTV, which does not need separate devices and extra cost. The systems called video-based fire surveillance systems use mainly a method extracting smoke or flame from an input image only. The smoke is difficult to extract at night because of its gray-scale color, and the flame color depends on the temperature, the inflammable, the size of flame, etc, which makes it hard to extract the flame region from the input image. This paper deals with a intelligent fire surveillance system which is robust against the variation of the flame color, especially at night. The proposed system extracts the moving object from the input image, makes a decision whether the object is the flame or not by means of the color obtained by fuzzy color model and the shape obtained by histogram, and issues a fire alarm when the flame is spread. Finally, we verify the efficiency of the proposed system through the experiment of the controlled real fire.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.10
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• pp.3475-3489
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• 2014

Here we present a simple flame detection method for an infrared (IR) thermal camera based real-time fire surveillance digital signal processor (DSP) system. Infrared thermal cameras are especially advantageous for unattended fire surveillance. All-weather monitoring is possible, regardless of illumination and climate conditions, and the data quantity to be processed is one-third that of color videos. Conventional IR camera-based fire detection methods used mainly pixel-based temporal correlation functions. In the temporal correlation function-based methods, temporal changes in pixel intensity generated by the irregular motion and spreading of the flame pixels are measured using correlation functions. The correlation values of non-flame regions are uniform, but the flame regions have irregular temporal correlation values. To satisfy the requirement of early detection, all fire detection techniques should be practically applied within a very short period of time. The conventional pixel-based correlation function is computationally intensive. In this paper, we propose an IR camera-based simple flame detection algorithm optimized with a compact embedded DSP system to achieve early detection. To reduce the computational load, block-based calculations are used to select the candidate flame region and measure the temporal motion of flames. These functions are used together to obtain the early flame detection algorithm. The proposed simple algorithm was tested to verify the required function and performance in real-time using IR test videos and a real-time DSP system. The findings indicated that the system detected the flames within 5 to 20 seconds, and had a correct flame detection ratio of 100% with an acceptable false detection ratio in video sequence level.

• Fire Science and Engineering
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• v.32 no.3
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• pp.42-50
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• 2018

The effect of sub-grid turbulence and combustion models on the mean flame height in a heptane pool fire according to the Fire Dynamics Simulator (FDS) version (5 and 6) based on Large Eddy Simulation (LES) was examined. The heat release rate for the fire simulation was provided through experiments performed under identical conditions and the predictive performance of the mean flame height according to FDS version was evaluated by a comparison with the existing correlation. As a result, the Smagorinsky and Deardorff turbulence models applied to FDS 5 and 6, respectively, had no significant effects on the mean flow field, flame shape and flame height. On the other hand, the difference in pool fire characteristics including the mean flame height was due mainly to the difference in the mixture fraction and Eddy Dissipation Concept (EDC) combustion models applied to FDS 5 and 6, respectively. Finally, compared to FDS 6, FDS 5 provided the predictive result of a significantly longer flame height and more consistent mean flame height than the existing correlation.

• Fire Science and Engineering
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• v.23 no.6
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• pp.10-15
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• 2009

Flame height calculation in a forest fire is a crucial part of predicting horizontal or vertical flame spread flared by radiation heat transfer. Flame height, which is one of the flame characteristics, can be estimated by the average height of luminous flame. This research relied on flame height observation test on P. densiflora surface fuel bed, which are surface combustibles in a forest, and calorimeter to measure Heat Release Rate, thus produced $H_f=0.027(\dot{Q'})^{2/3}$, flame height calculation equation for surface fuel. The research did not take into consideration such conditions as external velocity, slope and other variables that could affect flame height. According to comparison among experiment results, calculation results of the above formula and those of existing Heskestad formula (1998), it was found that standard error in fallen pine needles between experimental results and calculation results of the above formula amounts to 0.08, whereas standard error in same plant between experimental results and calculation results of existing Heskestad formula amounts to 0.23.