• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.5
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• pp.9-15
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• 2010

Recently, the high-compressive strength concrete where the use is extending was weak in fire because of spalling that was occurring with rise of internal vapor pressure by high temperature. For preventing spalling of high-strength concrete in fire, Organic fibers have been using in concrete generally. By melting of organic fibers in concrete in fire, the internal moistures of concrete moves quickly to the outside, and so, preventing of spalling of high-strength concrete. But this method will be able to prevent the spalling of high-strength concrete, but makes the decrease of the concrete strength after fire. This study make a comparison between properties of preventing of spalling and remaining compressive strength of concrete using intumescence Alkali-Silicates fire-resistant material and that of concrete with organic fibers. Using organic fibers for preventing of spalling of concrete are P.P and Nylon fibers, and anti-fire intumescence material for protection of concrete surface is alkali-silicate materials. Fire resistance test executed as long as 3 hr under the flame temperature $1,200^{\circ}C$ over. In the case of concrete with P.P fibers, don't occurred the spalling, but the remaining compressive strength will not be able to measure, the concrete using intumescence Alkali-Silicates system fire-resistant material is not only preventing of the spalling but also the remaining compressive strength maintained until the maximum 96%.

• Journal of Korean Society of Steel Construction
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• v.27 no.2
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• pp.143-153
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• 2015

In this paper, the standard fire resistance test under load and associated numerical study were carried out to evaluate the fire resistance of unprotected partially encased beams and slimfloor beams. The temperature evolution and the deflection increase of the composite beam specimens were investigated and the effects of the key behavioral parameters including the load ratio, the reinforcement, and the fire exposure were analyzed. The test results showed that the temperature rise of the partially encased beams and slimfloor beams is considerably slow compared to the conventional H-shape composite beams. Up to at least 90 minutes, the reinforcements in the partially encased composite beams maintained below the temperature at which the cold steel strength is sustained. Unprotected partially encased beams and slimfloor beams in the experimental program achieved the fire resistance more than 2 hours according to the limiting deflection criteria. This implies that unprotected partially encased beams and slimfloor beams can be very promising alternatives to enhancing the fire resistance of steel beams. This study also conducted the fully coupled thermal-stress analysis by using the commercial code ABAQUS to the thermal and structural behaviour of composite beams in fire. The numerical predictions provide acceptable correlations with the experimental results.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.7
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• pp.782-790
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• 2016

When a fire occurs on a ship that has mechanical ventilation facilities, the air supply and exhaust systems directly effect smoke diffusion. And there is a high possibility that occupant's visibility will be harmed because of smoke. In this study, the effects and risks of air supply and exhaust systems with regard to smoke diffusion given a shipboard fire analyzed with a Fire Dynamic Simulator(FDS). Suggested measures are also provided for using air supply and exhaust systems more efficiently. The results showed that, when air supply and exhaust systems were both working at the time of a fire, rather than stopping these systems as previously encouraged, continuing to operate both was an effective measure to gain evacuation time. When a fire occurred and the exhaust system was operating, also starting the air supply system near the origin of the fire was another effective approach to gain evacuation time. However, when only the air supply system was operating and a fire occurred, the air supply system accelerated smoke diffusion, so it was necessary to stop the air supply system to detect smoke diffusion as much as possible.

• Journal of the Korea Concrete Institute
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• v.23 no.3
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• pp.377-384
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• 2011

Although concrete is considered as fire proof materials, high strength concrete shows severe material and structural damages when exposed to fire. To understand such damages in high strength concrete structures, the effects of various design parameters and fire condition on the thermal behaviors of high strength concrete structures are investigated in this study. In order to achieve this goal, fire tests are performed on high strength concrete columns with different fire conditions and design parameters including cross sectional area, cover thickness, and reinforcement alignment. To investigate thermal behaviors, temperature distributions and amount of spalling are measured. In overall, the columns show rapidly increasing inner temperatures between 30~60 mins of the fire tests due to spalling. In detail, the higher temperature distributions are observed from the columns with the larger cross section and less cover thickness. Moreover, among the columns with same reinforcing ratio, larger number of reinforcements with the smaller diameter causes the higher temperature distribution. The findings from the experimental study allow not only understanding of thermal behaviors of high strength concrete columns under fire, but also guidance in revising fire safety design.

• The Korean Journal of Emergency Medical Services
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• v.14 no.2
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• pp.13-24
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• 2010

Objective : The purpose of this study is to understand the status of continuing education of the EMTs of the Korean fire department, to identify demand of them for content, method, and forms of the education, and to present basic data for developing more efficient, effective continuing education programs. Methods : The subjects of this study were 850 of the EMTs of the Korean fire department who work for fire stations located in Seoul and part of Gyeonggi-do and directly provide critical care in the field. The data was collected between February 8 and 28, 2010. Using SPSS 17.0 program, we obtained frequencies percentages, means, and standard deviations, and performed independent two sample t-test, one way ANOVA, and Cronbach's ${\alpha}$. Results : 1) As for status of the existing continuing education for of the EMTs of the Korean fire department, in general, the hour of each education was "less than four hours" (51.2%), the instructors of the education were "doctors" (65.2%), the method of the education was "lecture" (83.3%), the material for the education was "educational materials and slides" (97.2%), and the results from the education were "not helpful in job" (55.1%). 2) The effects of the EMTs of the Korean fire department were mean 2.44(${\pm}.51$), the ability was mean 2.40(${\pm}.50$), and the attitude was mean 2.49(${\pm}.57$) points. 3) As for the demands of the EMTs of the Korean fire department on the next continuing education, they preferred "the advanced cardiac life support(ACLS)" ($2.64{\pm}.62$) most in subject content, "investigating the demands of 119 emergency medical technicians annually" (44.1%) in methods to select subjects of the continuing education, "doctors and professors of Department of Emergency Medical Technology" in instructors of the education (190 persons, or 39.9%), "lectures with practices" in methods of the education (30.1%), and "One per year" (41.6%) and "less than four hours" (67.2%) in the period and hours of the text continuing education they hope. Conclusion : The continuing education for the EMTs of the Korean fire department conducts without accepting the demands of the technicians, In planning of the next continuing education, the results of this study suggest that it is needed to develop more various and professional educational program by active acquisition of the demands of the technicians.

• Journal of the Korean Institute of Gas
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• v.4 no.3 s.11
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• pp.9-18
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• 2000

Accident analysis are useful in the design stage of chemical plants and their surrounding structures. Also, analysis results are required for safety management of existing plants. In this paper, the fire and explosion effect by BTX released was evaluated. The computer program was prepared for accident analysis and adopted for evaluating the magnitude of fire (pool fire) and explosion (UVCE) effect. The thermal radiation was used as a measure of fire magnitude and the overpressure as a measure of explosion magnitude. And probit analysis was made for each case. As a case study, benzene tank model was used. The simulation results of explosion of benzene showed that the damage within 20 meters from the accident spot was severe and the damage beyond 60 meters was negligible. The simulation results of fire of benzene showed that the damage in summer is bigger than that in winter. And the damage of city located inland seems to be bigger than that of city in seaside. And thermal radiation effects was negligible beyond 40 meters-distance from the accident spot.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.644-648
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• 2019

This study examined effects of the wall thermal conductivity coefficients on the thermal fluid phenomenon of a compartment fire. The reduced scale compartment was 0.4 m in width, 0.6 m in length and 0.6 m in height with a fire-board, which has a thermal conductivity coefficient of $0.18W/m{\cdot}K$. The local temperature at a 0.37 m height and the overall heat release rate were measured under the following experiment conditions: a $0.12m^2$ opening area and $0.01m^2$ pool size of a gasoline fire. The numerical results obtained by the Fire Dynamic Simulation were compared with the experimentally measured temperature. The deviations were within 10 % in the period of the steady state for maximum heat release rate (4.8 kW). The numerical results show that the average temperature of the compartment wall decreases by approximately 71 % with increasing thermal conductivity coefficient from $0.1W/m{\cdot}K$ to $100.0W/m{\cdot}K$ on the fixed heat release rate.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.7 no.1
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• pp.35-51
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• 1994

This is the study on causes and remedies of hearing disturbance in chinese medical journals(1991-1993). The results were as follows. 1. The causes of sudden deafness(突發性耳聾) were usually fire in the liver(肝火).phlegmatic fire(痰火), deficiency of the vital function and essence of the kidney(腎虛), blood stasis or sludge due to stagnation of vital energy stagnation(氣滯血瘀). Remove endogenous heat or fire method(淸瀉火熱法). circulation of phlegm and dampness(運化痰濕). using tonics to cure disease due to deficiency of vital essence of both the liver and the kidney(滋補肝腎) were used for each treatment. 2.The causes of menieres disease were usually mental disturbance due to phlegmatit fire(痰化上搖). dampness-phlegm long standing(痰濕內停), water-dampness retention(水濕停滯), Method of remove heat and circulation phlegm(淸熱化痰法), method of remove water and dampness(利水渗濕法), invigorate function of the spleen and circulation of dampness method(健脾化濕法) were used for each treatment. 3. The causes of toxico-deafness(中毒性 耳聾) were usually heart, liver and kidney functional weakness(心肝腎虛), vital essence and blood weakness(氣血虛弱). Remove obstruction in the flow and circulation phlegm(通窮化痰), reinforce vital energy and tonify blood (補氣活血), using tonics to cure disease due to deficiency of vital essence of both the liver and the kidney(滋補肝腎) were used for each treatment. 4. The causes of deafness (耳聾), tinitus(耳鳴) were usually mental disturbance due to wind and heat(風熱上搖). flaming up of excessive heat of the liver(肝火上亢). exhaustion seat of reproductive essence in kidney(腎精虧虛). Remove endogenous heat and disperse wind(淸熱疏風). remove the fire of liver(淸肝瀉火), through nourish kidney check exuberance of yang(滋腎潛陽), nourish kidney yang(補腎陽). replenish vital energy and improve essential substance(益精血), blood activate for treatment of blood stasis(活血化瘀) were used for each treatment. 5. The effects of mainly used drugs were classified into method of water and dampness remove medicine(利水渗濕藥), nourishing liver and kidney medicine(補肝腎藥), improve blood and vital energy activate medicine(活血行氣藥), through nourish yan medicine check exuberance of yang(滋陰潛陽藥).

• Fire Science and Engineering
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• v.20 no.3 s.63
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• pp.15-20
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• 2006

In this study the flow characteristics of smoke and heat on a bank type platform of the underground subway station are studied numerically by considering two different emergency operation modes. Effects of the natural flow through the tunnel and the stair ways are considered in the numerical simulations by using the measured velocities presented in Part I as the boundary condition. Distributions of heat, smoke, visible range and toxic gas on the platform are analysed for different smoke extraction flowrates corresponding to the two different emergency operation modes. The numerical results show that the extraction flowrate affects the smoke control performance significantly by improving the smoke removal performance as the extraction flowrate is increased.

• Journal of Korean Tunnelling and Underground Space Association
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• v.7 no.1
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• pp.27-36
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• 2005

The objective of this study was to analyze the smoke movement and to investigate the effect of exhaust ventilation using by shafts for case of fire in long tunnels. Based on Froude modeling, the 1/50 scaled model tunnel (20 m long) was constructed by acrylic tubes and test were carried out systematically. The results of the shaft height test show that the effect on exhaust ventilation by a shaft delays the propagation time of backlayering, and the temperature decreases as the shaft height increases. If the fire occurs downstream of the shaft, the backlayering develops to get stronger by the shaft exhaust effect and then the propagation of CO and temperature increase along with propagation of CO. That is to say, in the case of fire downstream of the shaft, the shaft has the advantage of smoke exhaust effects, but it might result in a dangerous situation for the escaping passengers due to the more developed backlayering.