• Tunnel and Underground Space
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• v.20 no.4
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• pp.277-283
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• 2010

In this study, an experiment was conducted to evaluate the effectiveness of a exhaust engine in a basement karaoke fire. Exhaust engine was used as ventilation equipment in the experiment. Experiment was carried out in a basement karaoke for redevelopment. Temperature distribution and smoke concentration were evaluated according to the operation of an exhaust engine. Temperatures were decreased below $50^{\circ}C$ at the corridor due to the operation of the exhaust engine. Visibility was also improved.

• Fire Science and Engineering
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• v.24 no.3
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• pp.99-105
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• 2010

Ventilation fans utilized correctly can increase the effectiveness of fire fighters and survivability of occupants. It is possible to increase the pressure of a corridor to prevent the infiltration of smoke. In this study, experiments were carried out to evaluate ventilation effectiveness in corridor fires. Corridor used in the experiment was 20 m long. Heptane was used as a fuel. Temperature and visibility were measured in order to evaluate ventilation effectiveness according to the position of a vent. Vent distance ranged from 0 m to 4 m and height varied from 0 m to 1.5 m. When the vent was positioned 2 m long and 0.75 m high the result was most effective.

• 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.

• Korean Journal of Breeding Science
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• v.51 no.4
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• pp.424-427
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• 2019

A persimmon (Diospyros kaki L. Thunb.) cultivar, 'Chosi', which was a cross between 'Johongsi' and 'Nishimurawase' in 2000, was finally selected in 2010. 'Chosi' persimmon fruits were harvested in Sept. 19 in Naju, with a medium fruit size of 161 g, on average, and high soluble solids of approximately 15.3 °Bx. The flesh tastes good, with a crispy texture, and the juice is rich. The shape of the fruit is round oblate, and the skin color is orange; the appearance is graceful. Physiological disorders, such as stylar-end cracking or skin fine cracking, rarely occur in this cultivar. (Registration No. 7075)

• Fire Science and Engineering
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• v.19 no.1 s.57
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• pp.80-86
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• 2005

In this study effects of the natural wind and the forced smoke ejection by operating the exhaust fan are studied numerically to examine the flow characteristics of the smoke and heat generated from a fire on the platform of an underground subway station. Three different situations, including 1) the case with no natural wind and no exhaust fan operation, 2) the case with natural wind but no exhaust fan operation and 3) the case with no natural wind but exhaust fan operation, are considered for the numerical analyses. The numerical results show that the natural wind causes a rapid spread of the fire along the tunnel resulting in rapid spread of the smoke and heat over the platform which affects the escape. The operation of the exhaust fan also results in the rapid spread of smoke and heat over the platform, but the time required for reaching the safe escaping height of the smoke layer with the exhaust fan operation is much longer than that without the exhaust fan operation. The numerical results also show that the required capacity of the exhaust fan becomes larger when the effect of the natural wind is included.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.3
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• pp.89-94
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• 2009

The stack effect in high-rise buildings is expected more significant at nights in winter due to the large temperature difference between the inside and outside of the buildings. However, the existence of large openings such as natural ventilators on the floor may effect the position of neutral plane, smoke spread at fire and thus obstruct the door openings for rescue. In this paper, the vertical and horizontal pressure distribution with different openings of natural smoke ventilators was experimentally analyzed by investigating pressure differentials.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.260-261
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• 1999

산업시설 및 대형 발전설비에서 배출되는 아황산가스 및 질소산화물은 대기환경에 직접적으로 악영향을 미칠 뿐만 아니라, 오존의 생성과 고갈, 산성비의 출현등으로 지구 온난화와 같은 기후변화에 크게 기여하는 것으로 보고되고 있다. 기존의 습식 석회/석회석 탈황공정(FGD) 및 선택적 촉매/비촉매 탈질기술(SCR/SNCR)은 효과적인 상용기술로서 널리 연구개발되어 왔으나, 대단위 시설투자와 고비용, 2차 오염물질의 배출이 단점으로 지적되고 있다(Nam, 1999).(중략)

• Journal of Korean Tunnelling and Underground Space Association
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• v.19 no.3
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• pp.375-388
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• 2017

In order to solve the traffic congest and environmental issues, small-cross section tunnel for small car only is increasing, but there is not standard for installation of disaster prevention facility. In this study, in order to investigate the behavioral characteristics of thermal environment and smoke in a small cross section tunnels with a large port exhaust ventilation system, the A86, the U-Smartway and the Seobu moterawy tunnel, Temperature and CO concentration in case of fire according to cross sectional area, heat release rate and exhaust air flow rate were analyzed by numerical analysis and the results were as follows. As the cross-sectional area of the tunnel decreases, the temperature of the fire zone increases and the rate of temperature rise is not significantly affected by heat release rate. However, there is a difference depending on the change of the exhaust air flow rate. In the case of applying the exhaust air flow rate $Q_3+2.5Ar$ of the large port exhaust ventilation system, the temperature of the fire zone was 7.1 times for A86 ($Ar=25.3m^2$) and 5.4 time for U-smartway ($Ar=37.32m^2$) by Seobu moterway tunnel ($Ar=46.67m^2$). The CO concentration of fire zone also showed the same tendency. The A86 tunnels were 10.7 times and the U-Smartways were 9.5 times more than the Seobu moterway. Therefore, in the case of a small section tunnel, the thermal environment and noxious gas concentration due to the reduction of the cross-sectional area are expected to increase significantly more than the cross-sectional reduction rate.

• Resources Recycling
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• v.14 no.2
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• pp.10-18
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• 2005

The manufacture property of anhydrous calcium sulfate (anhydrite Ⅱ) from flue gas desulfurization (FGD) gypsum discharged from domestic thermoelectric power plants to apply as an auxiliary material of cement and concrete by high temperature treatment were investigated. The FGD gypsum was completely converted to anhydrite Ⅱ at the temperature of 700$^{\circ}C$ and the retention time of 1 hr. In the phase transformation process, particle size was also changed. The chemical composition, particle size and heat property of anhydrite Ⅱ made from the FGD gypsum were similar to them of natural gypsum. In the leaching test of sulfate ion (SO$_4^{2-}$) at the temperature of 90$^{\circ}C$ and the retention time of 1 hr, the amount of leached SO$_4^{2-}$ for the anhydrite Ⅱ that was sintered at 700$^{\circ}C$ for 1 hr was about 50 wt.% based on that of natural gypsum. In addition, the amount of leached SO$_4^{2-}$ for the anhydrite Ⅱ by adding the slaked lime of 3 wt.% decreased about 70 wt.% comparing with that of natural gypsum. In the application test, the compressive strength of cement and concrete manufactured by using the anhydrite Ⅱ as an auxiliary material were similar or superior compared with them of cement and concrete done by natural gypsum as an auxiliary material.

• Journal of Korean Society for Geospatial Information Science
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• v.1 no.2 s.2
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• pp.177-184
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• 1993

To obtain large scale precise geographical information in local area we determined external orientation parameters of camn exactly and conducted aerial photography using remote control airship loaded 35mm non-metric camera that produced systematic error coefficients. Ground control Points were determined by differential GPS. Therefore we can try to improve accuracy and economical efficiency. Also, it is suggested that remote control airship photogrammetry can be applied to make large scale topographic map using analytical plotter as calibrated accuracy.