• Title/Summary/Keyword: fire effects

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INTERNATIONAL ACTIVITIES ON FIRE RESEARCH

  • Hirano, Toshisuke
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 1997.11a
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    • pp.58-65
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    • 1997
  • In this paper presented are recent international activities on fire research. After a long history of exchanging ideas in individual international groups, the International Association for Fire Safety Science (IAFSS) was founded in 1985 at its first Symposium, and in 1988, it became a registered charity in England and Wales. The primary objectives of the association are encouraging research in the science of preventing and mitigating the adverse effects of fires and of providing a forum for presenting the results such research. In order to implement the objectives, the Association has held a series of Symposia. At the same time, regional activities have been performed to expand the activities of IAFSS into every individual country. The Asia-Oceania Association for Fire Science and Technology (AOAFST) was founded in 1992 at its first Symposium and the First European Regional IAFSS Symposium was held in Zurich in 1995. Extensive activities in fire research have been performed in Asian and Oceanian countries.

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Effect of Fire Safety Education Based on the Theory of Planned Behavior on the Fire Safety Behavior of Care Worker Trainees (계획된 행동 이론을 적용한 화재안전교육이 요양보호사 교육생들의 화재안전행동에 미치는 효과)

  • Byeon, Do-Hwa
    • Fire Science and Engineering
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    • v.33 no.1
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    • pp.147-155
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    • 2019
  • This study was a quasi-experimental research of a non-equivalent control group and non-synchronized design for analyzing the effects of fire safety education on care worker trainees. The subjects of the study were care worker trainees of the S Care Worker Institution: 57 trainees with 28 in the experimental group, and 29 in the control group. The research period was from May 21 to June 14, 2018 and the experiments focusing on fire safety education were performed once per week for a total of four times over the research period. The data were then analyzed using a ${\chi}^2-test$ and t-test. The results showed that fire safety education is an effective source of education for increasing the knowledge on fire safety, attitudes towards fire safety, perceived behavioral control on fire safety, behavioral intention on fire safety, and fire safety behavior in addition to being incredibly useful in practicing fire safety behaviors throughout their daily lives. On the other hand, the subjective norms on fire safety did not show any significant differences. Therefore, this paper suggests a follow-up study that should focus on analyzing the effects of the subjective norms on fire safety.

Effects of Fire on KDICical Properties of Soil and Runoff, and Phytomass in Pinus densiflora Forest Effects of Fire on KDICical Properties of Soil and Runoff, and Phytomass in Pinus densiflora Forest Effects of Fire on KDICical Properties of Soil and Runoff, and Phytomass in Pinus densiflora Forest (산화가 소나무림의 토양과 유출수의 화학적 성질 및 식물량에 미치는 영향)

  • Choung, Yeon Sook;Joon Ho Kim
    • The Korean Journal of Ecology
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    • v.10 no.3
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    • pp.129-138
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    • 1987
  • In a red pine (Pinus densiflora) forest, changes of pH, electric conductivity, total carbon, total nitrogen, available phosphate and available potassium in soil and runoff have been studied at intervals for 1 year after early spring fire. Phytimasses of herb and shrub were measured following the current and the subsequent year. The pH, E.C., total nitrogen and phosphate of soil in burned site wee 1.1, 1.5, 1.6 and 2.0 times higher than in unburned site, respectively. But potassium showed no significant difference. A rise in pH, E.C., and total nitrogen in burned site were maintained throught the study period while phosphate maintained 4 months after the fire. The E.C., total carbon, $NO_2-N$ and $NH_4-N$ of runoff in burned site were 1.3, 1.3, 1.3 and 29.0 times higher than in unburned site, respectively, while $NO_3-N$ in unburned site was 4 times higher than in burned site. In burned site, phytomasses of herb and shrub were 148 and 33% of unburned site in a current year and 107 and 51% in a subsequent year, respectively. The considerable amount of increase in soil nutrient after the fire was conserved by the uptake of the fast regrowing plants and by the immobilization of $NH_4=N$.

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A Numerical Study for Fire Safety Evaluation of the Multi-story Residential Buildings -The Effects of the Openings of Stairwell on Fire Characteristics- (다세대주택의 화재안전평가에 대한 수치해석 연구 -계단실 개구부의 개폐가 화재특성에 미치는 영향-)

  • Jeon, Heung-Kyun;Choi, Young-Sang;Choo, Hong-Lok
    • Fire Science and Engineering
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    • v.21 no.3
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    • pp.15-23
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    • 2007
  • In the events of a fire in the residential building, highly flammable polyurethane foam sofa produce toxic smokes. In this type of fire, the residents of the building can be gotten into the difficulties of evacuating from the fire places or may be to death due to a lot of hot toxic gases. In this study, CFD simulations were carried out to study the effects of the openings of stairwell on the fire characteristics of fire room and stairwell. Also, analysis of fire hazard based on the tenability limits of fire and FED(fractional effective dose) was performed to evaluate the life safety of the residents of the building. In the fire room, maximum temperature was about $290^{\circ}C$, maximum CO concentration was about 4,740 ppm, and the time to incapacitation of residents in fire room was about t=144 s. In the stairwell, temperature and CO concentration in the condition of openings to be open were even lower than those in it to be closed. Time to the tenability limit with respect to smoke visibility in the stairwell with openings, which was open, was shorter than that of it without openings to be open. It has been shown from this study that opening the stairwell openings is able to decrease the fire hazards to the life safety in the multi-story residential building fire.

Numerical Analysis on Interaction between Fire Flame and Water Mist according to the Variation of Nozzle Performance (노즐 특성 변화에 따른 미분무수와 화염과의 상호작용에 관한 수치해석)

  • Bae, Kang-Youl;Chung, Hee-Taeg;Kim, Hyoung-Bum
    • Proceedings of the KSME Conference
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    • 2007.05b
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    • pp.2983-2988
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    • 2007
  • In the present study, the numerical investigation on the effects of water-mist characteristics has been carried out for the fire suppression mechanism. The FDS are used to simulate the interaction of fire plume and water mists, and program describes the fire-driven flows using LES turbulence model, the mixture fraction combustion model, the finite volume method of radiation transport for a non-scattering gray gas, and conjugate heat transfer between wall and gas flow. The numerical model is consisted of a rectangular enclosure of $L{\times}W{\times}H=1.5{\times}1.5{\times}2.0m$ and a water mist nozzle that be installed 1.8m from fire pool. In the study, the parameters of nozzle for simulation are the droplet size and the spray velocity. Finally, the droplet size influences to fire flume on fire suppression than spray velocity because of the effect of terminal velocity, and the optimal condition for fire suppression is that the droplet size and the spray velocity are $100{\mu}m$ and 20m/s, respectively.

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Effects of Spray Characteristics of Water Mist on The Extinction of a Liquid Pool Fire (분무수 분무특성이 액체연료 Pool 화염의 소화에 미치는 영향)

  • Kim, Ho-Young;Oh, Sang-Youp;Chung, Jin-Taek
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.12
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    • pp.1591-1599
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    • 2004
  • A series of experiments were conducted to study the effectiveness of the extinction of a liquid pool fire with two different water atomizing nozzles. Fire source is a small-scale circular stainless steel pan of 120mm in diameter with the fuels of hexane and ethanol. K-type thermocouples were used to measure the flame and fuel temperature along the pool centerline and under fuel surface. A digital camera was used to visualize the process of the fire suppression. The experimental results show that water mist droplet size is l15∼180${\mu}{\textrm}{m}$ with nozzle A and 130∼190${\mu}{\textrm}{m}$ with nozzle B. The extinguishing time of pool fire was reduced with the increase of pressure. When water droplets are small, they do not reach the flame base since they may be deflected or evaporated by the fire plume. However, influence of flow rate is more important than droplet size on fire extinction. Among the fire extinction mechanisms, drop of flame temperature is superior to suffocation of $O_2$ concentration.

Implementation of Image based Fire Detection System Using Convolution Neural Network (합성곱 신경망을 이용한 이미지 기반 화재 감지 시스템의 구현)

  • Bang, Sang-Wan
    • The Journal of the Korea institute of electronic communication sciences
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    • v.12 no.2
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    • pp.331-336
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    • 2017
  • The need for early fire detection technology is increasing in order to prevent fire disasters. Sensor device detection for heat, smoke and fire is widely used to detect flame and smoke, but this system is limited by the factors of the sensor environment. To solve these problems, many image-based fire detection systems are being developed. In this paper, we implemented a system to detect fire and smoke from camera input images using a convolution neural network. Through the implemented system using the convolution neural network, a feature map is generated for the smoke image and the fire image, and learning for classifying the smoke and fire is performed on the generated feature map. Experimental results on various images show excellent effects for classifying smoke and fire.

Predicting residual moment capacity of thermally insulated RC beams exposed to fire using artificial neural networks

  • Erdem, Hakan
    • Computers and Concrete
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    • v.19 no.6
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    • pp.711-716
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    • 2017
  • This paper presents a method using artificial neural networks (ANNs) to predict the residual moment capacity of thermally insulated reinforced concrete (RC) beams exposed to fire. The use of heat resistant insulation material protects concrete beams against the harmful effects of fire. If it is desired to calculate the residual moment capacity of the beams in this state, the determination of the moment capacity of thermally insulated beams exposed to fire involves several consecutive calculations, which is significantly easier when ANNs are used. Beam width, beam effective depth, fire duration, concrete compressive and steel tensile strength, steel area, thermal conductivity of insulation material can influence behavior of RC beams exposed to high temperatures. In this study, a finite difference method was used to calculate the temperature distribution in a cross section of the beam, and temperature distribution, reduction mechanical properties of concrete and reinforcing steel and moment capacity were calculated using existing relations in literature. Data was generated for 336 beams with different beam width ($b_w$), beam account height (h), fire duration (t), mechanical properties of concrete ($f_{cd}$) and reinforcing steel ($f_{yd}$), steel area ($A_s$), insulation material thermal conductivity (kinsulation). Five input parameters ($b_w$, h, $f_{cd}$, $f_{yd}$, $A_s$ and $k_{insulation}$) were used in the ANN to estimate the moment capacity ($M_r$). The trained model allowed the investigation of the effects on the moment capacity of the insulation material and the results indicated that the use of insulation materials with the smallest value of the thermal conductivities used in calculations is effective in protecting the RC beam against fire.

Effects of Forest Fire on the Forest Vegetation and Soil(IV) (황폐산지(荒廢山地)에서의 산불이 삼림식생(森林植生) 및 토양(土壤)에 미치는 영향(影響)에 관(關)한 연구(硏究)(IV))

  • Woo, Bo-Myeong;Lee, Heon-Ho
    • Journal of Korean Society of Forest Science
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    • v.78 no.3
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    • pp.302-313
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    • 1989
  • To investigate the effects of forest fire on the change of vegetation and soil conditions by the lapse of time, the 5th soil survey and vegetation analysis were carried out in July of 1988 at the rocky areas of Mt. Kwanak, where ground fire broke out 5 years ago. Three-year increasing trends of organic matter content, the value of pH, and total nitrogen content stabilized after the restoration of the vegetation. By the comparison of the occurrences of the species for 5 years after the forest fire, woody and herbaceous plants were categorized into 4 groups, i,e., invasive, sensitive, tolerant, and neutral species to the forest fire. Although such diversity indices as the species diversity and similarity index indicate that the restoration of damaged vegetation to the original species composition was proceeded for the period, the restoration of vegetation to the original crown closure and tree growth was not proceeded yet.

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The Effects of the Area of Openings on the Performance of a $CO_2$ Extinguishing System -The CFD Simulations of the Oil Surface Fire in a Machine Room- (개구부 면적이 $CO_2$ 소화설비의 소화성능에 미치는 영향 -기계실 석유 표면화재의 CFD simulations-)

  • Jeon, Heung-Kyun;Choi, Young-Sang;Park, Jong-Tack
    • Fire Science and Engineering
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    • v.22 no.1
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    • pp.1-9
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    • 2008
  • Carbon dioxide($CO_2$) agent, which has more safely extinguished fire than any other gaseous fire extinguishing agents, has been widely used in various protected enclosures and types of fires. According to the concept of performance-based design(PBD). $CO_2$ extinguishing system to be designed is needed to be evaluated for the performance of fire suppression with possible fire scenarios in an enclosure. In this paper, CFD simulations were carried out to study the effects of opening area on the performance of $CO_2$ extinguishing system and the flow characteristics in the machine room of $100m^3$ in which kerosene spill fire happened. This study showed that time of fire suppression increased linearly in proportion to the size of opening area, and fires for each model were completely suppressed prior to the end of discharge of $CO_2$ agent. It was shown that mass flow rate through opening was influenced by the combined effects of heat release rate of fire and discharge of $CO_2$ agent. After $CO_2$ agent was completely discharged, oxygen concentrations in enclosures for each model were lower than the limit concentration of combustion.