• Fire Science and Engineering
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• v.23 no.5
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• pp.90-95
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• 2009

The wind is very important factor in forest fire spread. Flame spread has a change through wind pattern change in forest fire. In order to analyze the forest fire flame spread rate, change of flame tilt depending on wind may be considering first. This is be cause the flame spread rate varies by the flame tilt changed due to transfer of heat. Especially, as wind speed grow, flame gets closer to surface, heat transfer ratio increase, virgin fuel bed reaches ignition temperature more rapidly, and flame moves faster. This study deduces, through experiment and physical figure analysis, relations on the change behavior of flame tilt due to wind. The value of flame tilt angle calculated from the equation and the experiment value showed average error angle of $3.3^{\circ}$, which is relatively smaller than results of previous studies that used other coefficient. Froude number coefficient A can be calculated in the method provided in this research for estimation of flame tilt angle of virgin fuel bed with varying thermal properties. The research finding is expected to be applied to future studies on flame spread through numerical analysis of heat transfer.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.5
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• pp.57-62
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• 2009

Flame spread velocity to virgin surface fuel bed on a ground slope increases as the flame gets closer to the slope according to the change of a ground slope angle. The existing studies have generally adopted the theory that flame gets closer to the slope as the slope angle increases, without considering the change of flame tilt against the slope. In this study, experiments were made on the actual characteristics of the flame on slopes of various angles, and as a result, this study offers the flame tilt equation according to the slope angle, and derive correlation between flame tilt and flame spread velocity on slope conditions.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2003.04a
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• pp.112-117
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• 2003

• Korean Journal of Optics and Photonics
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• v.29 no.6
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• pp.233-240
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• 2018

In this paper, a design method to reduce fabrication errors in reflector shape of a test lamp for a flame detector is carried out. Although the test lamp should be operated in parallel with a high-intensity light, it is difficult to fix the small reflector that controls the central light during fabrication. To solve these problems, a small spherical reflector is designed to minimize the performance degradation for a light loss factor of less than 5%, even during tilt and decenter, and a spherical shape is proposed for a small reflector with little effect on the error when designing the optical system.

• The Journal of the Korea Contents Association
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• v.13 no.6
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• pp.40-47
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• 2013

In case of wild fire, early detection of wild fire is the most important factor in minimizing the damages. In this paper, we suggest an effective system that detects wild fire using a panoramic image from a single camera with PAN/TILT head. This enables the system to detect the size and the location of the fire in the early stages. After converting RGB image input to color YCrCb image, the differential image is used to detect changes in movement of the smoke to determine the regions which may be prone to forest fire. Histogram analysis of fire flame is used to determine the possibility of fire in the predetermined regions. In addition, image matching and SURF were used to create the panoramic image. There are many advantages in this system. First of all, it is very economical because this system needs only a single camera and a monitor. Second, it shows the live image of wide view through panoramic image. Third, this system can reduce the quantity of saved data by storing panoramic images.