• Title/Summary/Keyword: fire effects

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Analysis of Improvement Effects on Building Approach Vulnerability by Expanding Emergency Rescue Centers in Busan (부산지역 119구조대 증설을 통한 건축물 접근취약성 개선효과 분석)

  • Choi, Jun-Ho;Lee, Ji-Soo;Hong, Won-Hwa
    • Fire Science and Engineering
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    • v.29 no.5
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    • pp.79-87
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    • 2015
  • The placement of Korean fire-fighting administrative power in urban areas shows regional unbalance. In an ideal system, all citizens would be provided with equal fire protection and rescue services, but this is usually difficult to realize due to regional conditions or budget problems. In the case of Busan Metropolitan City, we deduced that it is impossible for half of the buildings to receive rescue services within 5 min, and the conditions are much worse for areas with long or wide fire-fighting service regions. The approach vulnerability for the existing emergency rescue squad locations was assessed. The results revealed that if a rescue team's location is shifted, the improvement effect will be virtually insignificant because of their geographical position. Therefore, this study suggests the establishment of additional rescue squads. It is proven that adding 5 rescue centers in the following locations could solve the problem of approach vulnerability: Bukbu, Gangseo, Geumjeong, Gijang, and Haeundae, in order of effectiveness. The number of buildings in the areas is 53,546.

Preliminary Leak-before Break Assessment of Intermediate Heat Transport System Hot-Leg of a Prototype Generation IV Sodium-cooled Fast Reactor (소듐냉각고속로 원형로 중간열전달계통 고온배관의 파단전누설 예비평가)

  • Lee, Sa Yong;Kim, Nak Hyun;Koo, Gyeong Hoi;Kim, Sung Kyun;Kim, Yoon Jea
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.12 no.1
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    • pp.126-133
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    • 2016
  • Recently, the research and development of Sodium-cooled Fast Reactors (SFRs) have made progresses. However, liquid sodium, the coolant of an SFR, is chemically unstable and sodium fire can be occurred when liquid sodium leaks from sodium pipe. To reduce the damage by the sodium fire, many fire walls and fire extinguishers are needed for SFRs. LBB concept in SFR might reduce the scale of sodium fire and decrease or eliminate fire walls and fire extinguishers. Therefore, LBB concept can contribute to improve economic efficiency and to strengthen defense-in depth safety. The LBB assessment procedure has been well established, and has been used significantly in light water reactors (LWRs). However, an LBB assessment of an SFR is more complicated because SFRs are operated in elevated temperature regions. In such a region, because creep damage may occur in a material, thereby growing defects, an LBB assessment of an SFR should consider elevated temperature effects. The procedure and method for this purpose are provided in RCC-MRx A16, which is a French code. In this study, LBB assessment was performed for PGSFR IHTS hot-leg pipe according to RCC-MRx A16 and the applicability of the code was discussed.

A study on the rules and the principles of the six-drugs mixing forming the prescription of Yukmijihwanghuan(六味地黃丸) (육미지황환(六味地黃丸)의 제방원칙(制方原則) 및 배합원리(配合原理)에 관(關)한 연구(硏究))

  • Kim, Yoon-Hyeon;Yoon, Chang-Yeol
    • Journal of Korean Medical classics
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    • v.23 no.6
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    • pp.1-14
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    • 2010
  • The conclusions after studying the rules and the principles of the six-drugs mixing forming the prescription of Yukmijihwanghuan(六味地黃丸) are as follows: 1. Yukmijihwanghuan cares for the three viscera; the liver, the spleen and the kidney and the three entrails; the urinary bladder, the gall bladder, and the stomach and it strengthens them as well. The drug can be used mainly for the cure of the Three Yang Channels of Foot and the Three Yin Channels of Foot. 2. The three drugs of Yukmijihwanghuan; Rehmanniae Radix, Dioscoreae Rhizoma, Corni Fructus altogether has the tonifying effect and the other three; Alismatis Rhizoma, Moutan Cortex, Poria has the purging effect. The first three kinds of drugs tonifies and the last three kinds of drugs purges. While these two groups of drugs are pitted against each other, they also balance each other harmoniously increasing the curative effect(remedial[curative] value). 3. Yukmijihwanghuan cools off the lung which is under metal category, helps the spleen, an earth category to be strong. It also adds the Water Qi to the kidney so that it stabilizes the Fire Qi. 4. Yukmijihwanghuan helps the kidney strongly, helps the urine to be excreted well, cools down the Fire Qi and makes dry things wet. 5. Rehmanniae Radix, the principal drug of Yukmijihwanghuan and Corni Fructus, the minister drug of the medicine have a taste of thick and are materially heavy. The two drugs do the descending action that it tonifies Yin Qi and adds Essence of Life. The other ingredients of Yukmijihwanghuan; Moutan Cortex, Poria, Alismatis Rhizoma have effects on lowering the Fire Qi. If Fire Qi descends, then Water Qi ascends. Yukmijihwanghuan has an efficacy of lowering Fire Qi and increasing Water Qi.

An Experimental Study on the Mechanical Properties of Ductile Outline Form and Fire Resistance of High Strength RC Column (고인성 외곽 거푸집의 역학성능 및 이를 활용한 고강도 RC기둥의 내화성능에 관한 실험적 연구)

  • Rho, Hyoung-Nam;Kim, Jae-Hwan;Kim, Yong-Ro;Kim, Wook-Jong;Kwon, Young-Jin;Lee, Sang-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2008.11a
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    • pp.199-203
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    • 2008
  • With recent trend in domestic and global market requiring architectures' conversion into skyscrapers seasoned with the features of landmarks, structural problems in relation with explosive spatting during fire emergencies are arising as controversial issues. Accordingly, many productive researches have been made in relation to the reinforcement techniques for improving fire resistance and the number of applications in the field is gradually increasing. In this study, a ductile outline form using ECC (Engineered Cementations Composites) was made with improvements on the structure and fire resistance to examine its applicability. Also, currently in Japan, the number of studies and applications is increasing focusing on reduction of construction time and improvement of workability with application of Half-PCa method. However, using such method of construction, large structural members decrease the utilization of space and architecture-wise, there is a disadvantage of the weight increase. Therefore, in such context, it would be worth reducing the weight of the structural members by reducing the size using ECC. In addition, its excellent pseudo strain-hardening due to fiber may have great effects on seismic designs. In the mean time, this study planned 3 equal conditions for mix water, PVA fiber and additives excluding binder and refractory to evaluate the mechanical properties of resistance against pressure and internal force. Finally, an evaluation was executed on the fire resistance of the newly made ductile outline form. As a result, from ECC-I to ECC-III, all showed excellent mechanical properties due to pseudo strain-hardening and in the fire resistance test conducted with ISO 834 heating curve, most of them tended to be in the range of the reference temperature (538℃-180min), so there was no occurrence of any explosive spatting.

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Experimental study of extinguishment of the pure diffusion flame using water spray (수분무를 이용한 순수확산화염의 소화에 관한 실험적 연구)

  • Jang, Yong-Jae;Kim, Myeong-Bae;Kim, Jin-Guk
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.2
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    • pp.624-631
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    • 1996
  • This study describes extinguishment mechanism of the purely buoyant diffusion flame using the water spray. Experiments are systematically carried out for the oul pool fire with the six different atomizing nozzles. From the measurement of burning rate which represents the combustion intensity of fire, it is observed that the water spray is able to act to enhance fire rather than to extinguish fire. The air entertainment due to the water spray is visualized to understand this phenomenon, acting to enhance fire. In order to observe effects of droplet size on fire extinguishment, and amount of water which reaches the flame base, fuel surface, and mean diameter of droplets are measured. When water droplets are too small, they do not reach the flame base because they can the water spray having too small doplets is ineffective for extinguishment of the oil fire.

Inhibitory Effect of adding Phase Change Material (PCM) to Fire Fighter Protective Clothing on Burn Injuries (Phase Change Material (PCM) 소재 적용 소방보호복의 화상발생 억제효과에 관한 연구)

  • Lee, Jun Kyoung
    • Fire Science and Engineering
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    • v.30 no.3
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    • pp.16-22
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    • 2016
  • Fire fighters rely on fire fighter protective clothing (FFPC) to provide adequate protection in the various hazardous environments. To enhance its protection performance, the FFPC material must be thick and thus it is difficult to achieve weight reduction. One of the methods of overcoming this problem, the addition of phase change material (PCM) to FFPC, is a new technology. In previous studies, the researches was mostly related to the temperature characteristics of the fibers incorporating PCM, but little information is available about its effect on burn injuries. Thus, in this study, the inhibitory effects of adding PCM to FFPC on second degree burns were investigated through numerical calculations. Thermal analyses of biological tissues and FFPC with embedded PCM exposed to several fire conditions causing severe tissue damage were studied by using a finite difference method based on the Pennes bio-heat equation. FFPC with embedded PCM was found to provide significantly greater protection than conventional fire fighting clothing, because the heat of absorption due to the phase change within the material is used to limit the heat conduction of the material.

Influences of Forest Fire on Forest Floor and Litterfall in Bhoramdeo Wildlife Sanctuary (C.G.), India

  • Jhariya, Manoj Kumar
    • Journal of Forest and Environmental Science
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    • v.33 no.4
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    • pp.330-341
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    • 2017
  • Tropical forests play a key role for functioning of the planet and maintenance of life. These forests support more than half of the world's species, serve as regulators of global and regional climate, act as carbon sinks and provide valuable ecosystem services. Forest floor biomass and litterfall dynamics was measured in different sites influenced by fire in a seasonally dry tropical forest of Bhoramdeo wildlife sanctuary of Chhattisgarh, India. The forest floor biomass was collected randomly placed quadrats while the litterfall measured by placing stone-block lined denuded quadrat technique. The seasonal mean total forest floor biomass across the fire regimes varied from $2.00-3.65t\;ha^{-1}$. The total litterfall of the study sites varied from $4.75-7.56t\;ha^{-1}\;yr^{-1}$. Annual turnover of litter varied from 70-74% and the turnover time between 1.35-1.43 years. Monthly pattern of forest floor biomass indicated that partially decayed litter, wood litter and total forest floor were differed significantly. The seasonal variation showed that leaf fall differed significantly in winter season only among the fire regimes while the wood litter was found non significant in all the season. This study shows that significant variation among the site due to the forest fire. Decomposition is one of the ecological processes critical to the functioning of forest ecosystems. The decomposing wood serves as a saving account of nutrients and organic materials in the forest floor. Across the site, high fire zone was facing much of the deleterious effects on forest floor biomass and litter production. Control on such type of wildfire and anthropogenic ignition could allow the natural recovery processes to enhance biological diversity. Chronic disturbances do not provide time for ecosystem recovery; it needs to be reduced for ecosystem health and maintaining of the high floral and faunal biodiversity.

Effects of computer and demonstration scenario simulation using smart fire evacuation guidance on evacuation induction and time (스마트 화재대피 유도 컴퓨터 및 실증 시나리오 시뮬레이션이 피난 유도와 시간에 미치는 영향)

  • Shin, Dong-Min;Cho, Byung-Jun
    • Journal of Convergence for Information Technology
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    • v.11 no.12
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    • pp.244-253
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    • 2021
  • This study examined how the fire evacuation induction service system using a smartphone navigation application in the event of a fire affects the fire evacuation time, and the following conclusions were drawn. 1. The evacuation time was reduced by 22 seconds when the navigation application was used in computer scenario simulation. Even in the demonstration simulation, the evacuation time was reduced by 40 seconds when the navigation application was used. This indicates that the navigation application is effective in shortening the evacuation time in case of fire. 2. As a result of the demonstration scenario simulation, the time until the end of evacuation was 39 seconds faster in the case of evacuation guidance than in the case where it was not conducted. 3. No bottlenecks occurred in the evacuation route during the demonstration scenario simulation. As a result, there was a difference in the time required to complete the evacuation between the computer scenario simulation and the demonstration scenario simulation.

Analyses of Scenarios Based on a Leakage of Highly Compressed Air and Fire Anticipated in CAES (Compressed Air Energy Storage) Facility (압축공기에너지저장 시설에서 발생 가능한 압축공기 유출 및 화재 시나리오 분석)

  • Yoon, Yong-Kyun;Ju, Eun-Hye
    • Tunnel and Underground Space
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    • v.25 no.6
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    • pp.568-576
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    • 2015
  • In this study, scenarios based on the leakage of highly compressed air and fire occurrence turned out to be high risks in an operation stage of CAES facility were constructed and estimated. By combining Bernoulli equation with momentum equation, an expression to calculate an impact force of a jet flow of compressed air was derived. An impact force was found to be proportional to the square of diameter of fracture and the pressure of compressed air. Four types of fire scenarios were composed to evaluate an effects that seasonal change and location of fire source have on the spread behavior of smoke. Smoke from the fire ignited in the vicinity of CAES opening descended more quickly below the limit line of breathing than one from the fire occurred 10 m away from CAES opening, which is expected to occur due to a propagation of wave front of smoke. It was shown that a rate of smoke spread of the winter fire is faster than one of the summer fire and smoke from the winter fire spreads farther than one of the summer fire, which are dependent on the direction of air flow into access opening. Evacuation simulation indicated that the required safe evacuation time(RSET) of the summer and winter fires are 262, 670 s each.

Effects of Burnout on Job Stress and Ego-Resilience of Fire Officials (소방공무원의 직무스트레스와 자아탄력성에서 소진의 영향)

  • Lee, Hae-Young;Kim, Yeob-Rae
    • Fire Science and Engineering
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    • v.31 no.2
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    • pp.106-112
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    • 2017
  • This study examined the burnout intermediates between Fire officials' job stress and Ego-resilience. The objective of this study is to suggest a policy that improves Fire officials' Ego-resilience. This survey was given to 365 fire officials in northern Gyeonggi-do region and the data was analyzed by correlation analysis and regression analysis using SPPS 22.0. The hypothesis is the Fire officials' burnout would be related to Ego-resilience and the effect on Fire officials' job stress regarding Ego-resilience is associated with burnout. The results of the study are that unstable work and inadequate reward affect the measure of burnout, which manifests as sarcasm and job efficacy and reduces the Fire officials' Ego-resilience that results in a positive pointing of the future, emotion control and interest. The meaning of policy is as follows: First, Fire officials need to be given confidence in their work stability. Second, they have to receive social or financial rewards. Third, they require a continuous supporting policy that solves their tension, physical and mental fatigue. Finally, developing diverse educational programs will be needed to promote their Ego-resilience.