• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.67-70
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• 2008

As a part of the project on road tunnel fire safety system development, Quantitative Risk Assessment program was developed. In this study, We carried out Quantitative Risk Assessment with this program by using a factor of cross passage interval, warning announcement time and congestion ratio etc for 1km tunnel with natural ventilation. In the case of 250m below of cross passage interval, Risk value due to warning announcement time was a slightly changed. but if cross passage interval is more than 250m, expected fatalities in the same HRR(heat release rate) was sharp increased. As a result, Quantitative Risk Assessment program which was developed in this research project is possible to risk assessment with ventilation type, cross passage for evacuation and detection system response property etc. hereafter, this program look forward to use as a tool for road tunnel performance based design.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.76-81
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• 2007

The shopping center in underground passage increased for efficient space utilization in urban area. This study describes operation characteristics of all air type and hybrid type with local ventilation and fan coil unit fixed to ceiling. In order to compare energy saving, thermal environment and installation space, etc., integrated simulator with heat production and indoor distribution system is designed and constructed. Energy saving of the hybrid system is calculated as over 30% compared to conventional all air type. And also the results showed that humidity decreased about 6%, also indoor thermal distribution is improved as temperature variation of around $1^{\circ}C$.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2989-2994
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• 2008

The shopping center in underground passage for efficient space utilization is increased in urban area. This study describes operation characteristics of HVAC systems with ventilation and individual heating and cooling unit for shopping center in underground passage. In order to compare energy saving, thermal environment and installation space, etc., an integrated simulator with heat production and distribution system was designed and constructed. Energy delivery efficiency is improved over 20%, and energy saving of the hybrid system is calculated as over 30% compared to conventional all air type in the case of heating. And also the results showed that humidity decreased about $5{\sim}6%$, also characteristics of thermal control is improved over 34%.

• Journal of Environmental Science International
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• v.16 no.4
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• pp.467-477
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• 2007

A numerical study with Envi-met model is experimented to investigate the characteristics of wind pattern in apartment complex. In all case, most conditions such as wind speed, temperature, and surface features are considered as the same, but wind direction is the only different factor. The wind directions considered in this study have a meaning of prevailing wind direction. When the prevailing wind with the direction of $170^{\circ}$ blows into the complex, the ventilation passage toward the outside of complex is formed and the stagnation of air is not expressed. In case of having the direction of $300^{\circ}$, most evident ventilation passages are composed. When the inflow wind direction is the northeast, $30^{\circ}$, there is some possibility of stagnation phenomenon. This is because the arrangement of buildings makes a right angle with the inflow wind direction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1523-1528
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• 2008

In this study, the ventilation system of connection passage and elevator hall of underground parking lot in apartment houses is investigated to extract the data for the installation and the application by the experimentation. In case of the elevator hall, actual air exchange rate is predicted fivefold higher than air exchange rate by infiltration and exfiltration. Ventilation system is installed good by supply air and return air. As the next best thing, it is installed by supply air because of IAQ control. The temperature of connection passage and elevator hall uniformly with $7{\sim}8^{\circ}C$, is maintained even if the operating condition of ventilation system is different. Therefore, the installation of the preheater, which is installed at the inlet of ventilation system for the cold draft in winter, is not essential in southern area of Korea.

• Journal of the Korean Society for Railway
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• v.12 no.1
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• pp.9-15
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• 2009

In this study, the l/35 reduced-scale model experiment were conducted to investigate designed ventilation system performance at rescue station in tunnel fire. A model tunnel with 2 mm thick of steel, 10 m long, 0.19 m high and 0.26m was made by using Froude number scaling law. The cross-passages installing escape door at the center. were connected between accident tunnel and rescue tunnel. The n-heptane pool fire, $4cm\times4cm$, with heat release rate 698.97W were used as fire source. The fire source was located in the center and portal of accident tunnel as Worst case.. An operating ventilation system extracted smoke amount of 0.015 cms. The smoke temperature and carbon monoxide. concentration in cross-passage were measured to verify designed ventilation system. The results showed that, in center fire case without ventilation in accident tunnel, smoke did not propagated to rescue station. In portal tire case, smoke spreaded to rescue station without ventilation. But smoke did not propagated to rescue station with designed ventilation.

• International Journal of Air-Conditioning and Refrigeration
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• v.17 no.2
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• pp.45-51
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• 2009

Three-dimensional numerical analyses of mechanical ventilation system in vent shaft of subway in operation are carried out in relation with the different air flow passage of vent shaft and two ventilation operation modes of push/pull, The ventilation characteristics of vent shaft with regard to the shape change are evaluated. And the air flow rate through the vent shaft by ventilation system is measured within subway in operation to assess the accuracy and applicability of the numerical analysis method. The decrease of air flow rate due to vent-shaft change are between 0.7 to 2.2% in the cases examined.

• Journal of Environmental Impact Assessment
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• v.20 no.2
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• pp.133-140
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• 2011

A numerical study with Envi-met model is experimented to investigate the characteristics of wind pattern in Gangwon innovation city. In all case, most conditions such as wind speed, temperature, and surface are considered as the same, but wind direction is the only different factor. The wind directions considered in this study have a meaning of prevailing wind direction. When the prevailing wind with the direction of $247^{\circ}$ blows into the city, the ventilation passage toward the outside of city is formed and the stagnation of air is not expressed. In case of having the direction of $270^{\circ}$, most evident ventilation passages are composed. When the inflow wind direction is the north, $0^{\circ}$, there is some possibility of stagnation phenomenon. The case where the representative wind direction of three kind will flow with development, in compliance with the building is caused by with screening effect of some and shows a true stagnation phenomenon, wishes in the park and flowing water and the greens area to be for a long time formed and the wind direction is maintained.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.163-167
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• 2008

In this study, the 1/35 reduced-scale model experiment were conducted to investigate designed ventilation effect on the smoke movement at rescue station fire in railway tunnel. A model tunnel with 2 mm thick, 10 m long, 0.19 m high and 0.26 m was made by using Froude number scaling law. The cross-passages installing escape door at the center were connected between incident tunnel and rescue tunnel. The n-heptane pool fires with heat release rate 698.97W were used as fire source. The fire source was located at the center and portal of incident tunnel as worst case. A operating ventilation system extracted smoke amount of 0.015 cms(cubic meters per second). The smoke temperature and CO gas concentration in cross-passage were measured to verify designed ventilation system. The result showed that, at center fire case without ventilation, smoke did not propagate to rescues station. In portal fire case, smoke spreaded to rescues station without ventilation. But smoke did not propagated to rescues station with designed ventilation.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1983.05a
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• pp.6.3-6
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• 1983

A total of 287 patients with foreign body in the air and food passage was treated in our unit between 1972 and 1982 and the following results were obtained : 1) The ratio between food and air passage was about 8 : 1. 2) The most common foreign bodies in the esophagus were coin (55.8%) and bone (28.5 %). Beans were the most common in the air passage (39.4%). 3) In sex distribution, there was no significant difference between male and females in the esophageal foreign bodies, but in the air passage male were prevalent (M : F = 57.9% : 42.1%). 4) In the age incidence, 61.8 % of the esophageal foreign bodies and 71 % of the foreign bodies in the air passage were under 5 Years of age. 5) The most prevalent site of Lodgement in the esophagus was the first narrowing (82.3 %). In the air passage, bronchial foreign bodies were more common and the right bronchus was the more frequent site (2 : 1). 6) In duration of lodgement, 62.2 % of esophageal foreign bodies and 55.2 % of foreign bodies in the air passage were removed within one day. 7) The most common complication of foreign bodies in the air passage was pneumonia (55.5%). 8) The removal of the foreign bodies in the air passage was performed by ventilation - bronchoscopy (84.3%). Two of 38 cases expired.