• 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.

• Fire Science and Engineering
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• v.28 no.6
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• pp.52-57
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• 2014

The present study suggests the fundamental method for the prediction time of the fire origin by analyzing the combustion phenomenon of inflammable material in the building structure. The heat release rate (HRR) with time variant is evaluated for the interphone as a inflammable material, which is opted from the fire incidents in the stairwell. the fire dynamics simulator (FDS ver. 6.1) is applied in order to analyze the difference of the smoke inflow time to the downstair from the fire event area with various fire pattern. The results show that the maximum inflow time difference for the case of the interphone made from ABS materials is about 4.93 times with the input conditions of heat flux values and the environment in the FDS for the fixed stairwell which composed of total volume $291.3m^3$, floorage $23.3m^2$ and the height of each floor 2.5 m. This research can be practical information for the application method of simulation scheme with experimental data to the fire Identification.

• Fire Science and Engineering
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• v.29 no.6
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• pp.119-128
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• 2015

A fire broke out in a working wood-burning stove and destroyed an idyllic house about two years after it was built. This study analyzed data provided through the court by the fire station, police station, fire insurance investigation agency, house construction company, and wood-burning stove maker Based on the fire pattern of low-temperature long-term ignition that remained in the studs, the fire was found to be caused by the conduction of heat in the fire box to the studs of the wall next to the wood-burning stove. A fire simulation showed that the low-temperature long-term ignition of the studs next to the wood-burning stove occurred because a hole was not made for ventilation in the chimney.

• Fire Science and Engineering
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• v.32 no.5
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• pp.40-45
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• 2018

This paper is an analysis of the influence of ceiling air conditioner airflow on fire detector response. In order to analyze the response characteristics of fire detector while forming air flow of a ceiling-type air conditioner, fire tests were carried out in accordance with ISO standard. This experiment was carried out in a fire test site of 10 m (width) ${\times}$ 7 m (length) ${\times}$ 4 m (height). As a result of the experiment, the response of fire detector shows a normal pattern that is delayed as the distance from the fire source is increased in the absence of the air conditioner, but it is confirmed that the pattern is not maintained in the strong air flow. When the air flow of air conditioner was strong, the response time was increased by 121% in the smoke detector and by 39% in the heat detector. In the case of ceiling type air conditioners, it is considered that the number of fire detectors should be increased, or a detector with high sensitivity should be installed for early detection of fire.

• Fire Science and Engineering
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• v.33 no.6
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• pp.126-131
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• 2019

Real-scale fire tests were performed on animal-origin foods using a gas stove with no overheating prevention device. When the animal-origin foods were ignited, a large quantity of white smoke and steam was generated from them; however, when they became dry and began to carbonize, a dark smoke was generated. Even after the gas stove was overheated for more than 5400 s, mackerel, pollack, chicken, etc., did not ignite. However, pork, beef, and tuna caught fire after 2643 s, 2819 s, and 6492 s of heating, respectively. The flame patterns of animal-origin foods were in the forms of a mixed laminar flow and a turbulent flow, and a halo pattern was produced. A sand glass form of the flame pattern was generated when a kitchen hood was operated, but a triangular flame pattern was produced when the kitchen hood was not operated. When the tuna in the pot was overheated, it spontaneously ignited after 6492 s, with the surface temperature of the kitchen hood rapidly rising to 464.5 ℃. Moreover, the temperature at the back of the pot, which was 6 cm away from the outer surface of the upper part of the pot, was 869 ℃ after 6660 s because of the radiant heat. The flame formed a sand glass pattern on the kitchen wall. When the kitchen hood was not operated, or when the flame grew lower than the height of the ceiling, a triangular pattern was formed.

• Fire Science and Engineering
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• v.34 no.2
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• pp.14-21
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• 2020

This paper presents the study of a fire risk to the backside of two miniatures of ISO 9705 2/5 using a lightweight partition for indoor space division and reproduction of the ISO 9705 test. An SGP partition, stud partition, glass wool panel, urethane foam panel, sandwich panel, and glass partition were selected as the test specimens, which are frequently used in construction. According to the ISO 9705 test standard, stabilization was achieved using a measuring device that recorded data before the ignition of a burner and continued recording for 120 s thereafter. After ignition was achieved, the power was increased to 300 kW for 600 s and then reduced to 100 kW for 600 s. The specimens were subsequently observed for 180 s, and the fire risk to the backside and the fire pattern of the wall unit were analyzed. Owing to the amount of heat generated by the ignition source, the maximum temperature of the backside was observed to be 67.7 ℃ for the SGP partition, 55.1 ℃ for the stud partition, 52.4 ℃ for the glass wool panel, 727.4 ℃ for the sandwich panel, 561 ℃ for the urethane foam panel, and 630.5 ℃ for the glass partition. In the cases of the sandwich and urethane foam panels, the explosion of flammable gas occurred by virtue of fusion of the interior materials. The reinforced glass was fractured owing to the temperature difference between the heat- and nonheat-responsive parts. Ultimately, the fire risk to the nearby section room was deemed to be high.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.2
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• pp.453-458
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• 2008

This study aimed to develop an evaluation reliability of Korean pattern identification for wind stroke. We studied 643 patients with stroke and made a list of registry for each of them. The present study analyzed 553 cases, in which the resident’s pattern identification agreed with the specialist’s one, and the cases included five differentiation pattern: the fire-heat pattern (114), the dampness-phlegm pattern (157), the static blood pattern (11), the Yin deficiency pattern (81), and the Qi deficiency pattern (190). This study showed that none of the Cronbach's alpha reached 0.700, which is the general reliable level. The average Cronbach's alpha of each symptoms was 0.353 for the dampness-phlegm pattern, 0.571 for the fire-heat pattern, 0.443 for the Qi deficiency pattern, 0.451 for the Yin deficiency pattern, and 0.302 for the static blood pattern. This suggests the possibility that each pattern identification could be coincided with other symptoms, and it also shows the limits of pattern identification of this study that narrows the symptoms of paralysis patients into only a single pattern. Continuous compliments and researches should be done referring to this matter. However, the internal consistency analysis of all the pattern identification showed that every Cronbach's alpha were within the range of 0.670 to 0.703, and the Cronbach's alpha of the whole symptoms was evaluated as 0.692, which makes the reliability of the pattern identification as itself almost satisfactory to the general reliable level, and therefore, significant. In the future, continuous clinical research to develope this pattern identification for wind stroke actually applicable to stroke patients needs to be made through accumulating more cases, improving the objectivity.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.40-43
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• 2011

전해 커패시터의 발열 메커니즘 및 소손 패턴 해석에서 최초의 출화는 1차측 전원으로 확인되었다. 전해 커패시터 외부의 방폭캡이 탄화되었고, 인접한 기판에도 탄화된 흔적을 확인되었으나 극성의 역사용, 과전압의 인가 및 금속한 충전 및 방전 등은 없었다. 전해 커패시터 내부를 X-ray 분석한 결과 전극 및 극판에는 이상이 없는 것으로 확인되었다. 부품 사양에 제시된 하한사양한계(LSL)는 144[${\mu}F$], 상한사양한계(USL)는 216[${\mu}F$]이며, 소손된 전해 커패시터의 공정능력분포(Cpk)가 1.21로 분석된 것으로 보아 공정 개선이 필요한 것으로 판단된다. 전해커패시터의 발열 메커니즘은 AC 과전압의 인가, 서지의 유입, 내부 온도의 상승, 기밀불량 등에 의해 지배되는 것을 알 수 있었다. 전해 커패시터를 설계할 때 고려사항은 적절한 전압의 인가, 정확한 등가직렬저항(ESR)의 연결, 급속한 충전 및 방전의 제어, 충분한 유전정접의 여유(margin) 확보 등이 중요한 요소이다.

• Fire Science and Engineering
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• v.34 no.4
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• pp.101-106
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• 2020

This study analyzed flame growth characteristics and carbonization patterns when floor materials were burned vertically using a needle flame produced for this study. It was found that PVC flooring was fire retardant and the area under direct flame contracted inward. Vertical combustion causes solidification in the form of a lump at the bottom and also generates soot in a pattern that progresses upwards. This study found that laminated flooring exhibited no fire retarding characteristics and that the laminated layer of its upper surface was destroyed by fire, causing irregular delamination. The carbonization ranges at the left and right sides were determined to be symmetrical. A vertical combustion test of a sample carpet showed that it exhibited no fire-retarding characteristics. It was observed that if heat accumulated in the carpet, the flame formed an ascending air current, and that when flammable materials were present around the flame, they further accelerated the diffusion of the flame. The carbonization pattern at the carpet surface exposed to direct flame revealed that the carpet surface had melted and had flown downwards and that many tiny holes formed on it.

• The Journal of Korean Medicine
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• v.20 no.2
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• pp.187-197
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• 1999

To assess the usefulness of tongue inspection for evaluating the Pattern identification in oriental medicine, we observed stroke patient's tongue and tongue coat and compared it with Pattern identification. The test group was composed of 85 acute stroke stage patients(within 72 hours of onset). Subjects were randomly selected from stroke patients admitted in the KyungHee University, Hospital of Oriental Medicine from December 1 1998 to June 30 1999. We took pictures of patient's tongue and tongue coat within 72hours from onset and checked Pattern identification at the same time. Tongues colored pale rose or red greatly outnumbered other colors. Tongue shape tended to be prickly or fissured, and tongue condition tended to be unflexible or deviated. Regarding tongue coat color, there were great amounts of yellow or clark yellow tongue coats, which were moist, thick or greasy in substance. The red tongue was significantly related to Fire-heat and deficiency of Yin syndrome, while faint white tongue to Damp syndrome(P=0.006). In terms of tongue coat, thin coat was related to Wind and Fire-heat syndromes, thick coat to Damp and Blood stasis syndrome, respectively (P=0.002). In conclusion, we thought that tongue inspection could be a useful Oriental medicine diagnosis in stroke.