• Proceedings of the SAREK Conference
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• 2006.11a
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• pp.68-68
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• 2006

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.124-132
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• 2010

To predict and analyze the rolling stock's fire growth is considered not only important factor in estimating hazard analysis of rolling stock, but also a primary factor in aspect of a rail load facility. Because it's could be regarded as a ignition source in risk assesment for the facility i.e. tunnel and station. However, currently, standardized method to predict and analyze the fire growth has not been completed yet. it is due to the fact that fire growth is not only depended on thermal property of interior materials, but also is affected dominantly by various factors such as ignition source (characterized by location, duration, and intensity), train running condition and in/exterior ventilation condition. Especially, ventilation condition is one of the most effective factor to affect fire growth in compartment space as noticed by under-ventilation fire condition. In this study, the effect of each ventilation condition on fire growth and load were examined through the numerical method through FDS (Fire Dynamics Simulator).

• Journal of the Korean housing association
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• v.17 no.2
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• pp.135-142
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• 2006

The purpose of this study is to obtain the fire safety for underground commercial space with analysing fire loads and ventilation factors. It was adopted the investigation method of field survey with commercial uses for more confidential data. The results of this study can be summarized as follows; 1) The ventilation factor shows $0.04{\sim}0.24m^{1/2}$ and it may develop ventilation-controlled fires which have much fire hazard more than fuel-controlled fires. 2) The highest value of fire load is $158.48kg/m^2$ and appeared in footwear shop which has the value $137.35kg/m^2$ for unfixed combustibles and $21.13kg/m^2$ for fixed combustibles. 3) The average value of burning rates which mean the velocity of fire development and the fire damage range is 0.143. Therefore it is desired to decrease the combustibles of compartment and is needed the method of dispersion arrangement of goods and storage to steel cabinet and so on.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.708-713
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• 2008

Various kinds of contaminant are generated from many kinds of interior construction materials, furniture and life articles. People of today living indoor most of the time are exposed to these kinds of contaminant. In this connection, people are exerting their efforts to reduce the occurrence of contaminant from the interior finish materials. And it is the actual condition that research is being actively made on the method of reducing contaminant by performing bake-out for newly constructed housings. Bake-out is the method of temporarily increasing the generation of the harmful contaminant quantity including VOCs and Formaldehyde emitting from construction materials or finish materials by increasing the interior temperature of the newly constructed buildings or improved or repaired buildings, and then removing it by mobilizing ventilation system. In this study, the researcher measured the effect of reduced concentration according to ventilation or non-ventilation of the newly constructed but not yet resident public housings during the bake-out in order to grasp the effect of reduced interior air contaminant according to the elapse of timeat the time of bake-out.

• Journal of Environmental Science International
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• v.15 no.10
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• pp.913-918
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• 2006

Despite the wide distribution of air pollutants, the concentrations of indoor air pollutants may be the dominant risk factor in personal exposure due to the fact that most people spend an average of 80% of their time in enclosed buildings. Researches for improvement of indoor air quality have been developed such as installation of air cleaning device, ventilation system, titanium dioxide$(TiO_2)$ coating and so on. However, it is difficult to evaluate the magnitude of improvement of indoor air quality in field study because indoor air quality can be affected by source generation, outdoor air level, ventilation, decay by reaction, temperature, humidity, mixing condition and so on. In this study, evaluation of reduction of formaldehyde and nitrogen dioxide emission rate in indoor environments by $TiO_2$ coating material was carried out using mass balance model in indoor environment. we proposed the evaluation method of magnitude of improvement in indoor air quality, considering outdoor level and ventilation. Since simple indoor concentration measurements could not properly evaluate the indoor air quality, outdoor level and ventilation should be considered when evaluate the indoor net quality.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.6
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• pp.822-826
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• 2009

In case of engine room of ship, it uses type 2 ventilation system which supplies outside air forcibly by engine room ventilation fan, and naturally discharges air to outlet through low-pressed casing. The advantage of type 2 ventilation is that it makes inside with bi-pressure status to discharge contaminated materials to outside naturally. However, there is a phenomenon that pressure is greatly different between outside and inside due to huge amount of air supply by engine room ventilation fan. Therefore, we went aboard a container vessel which is on test run to analyze differential pressure with micronanometer by engine load and by combustion air supply method of engine. As a result, as engine load decreases (50, 75, 100%), the differential pressure between outside and inside tends to increase by 35% average, and the difference of pressure was 6.5 times maximum by combustion air supply method of engine.

• The Korean Journal of Emergency Medical Services
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• v.22 no.1
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• pp.73-82
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• 2018

Purpose: The purpose of this study was to compare the tidal volumes and airway pressures of 3 mask-sealing methods (one hand C-E, two hands C-E, and one hand O-E) for ventilation treatment. Methods: The study subjects were 45 paramedic students. Tidal volume was measured for the three sealing methods by setting a ventilator, connecting it to the masks for 2 minutes, and using Respi-trainer software. Results: Regarding general characteristics, the group of men, in upper grades, and with practical training experience and experience and experience in the implementation of bag-valve-mask ventilation provided higher tidal volumes. Regarding physical characteristics, larger hands and greater grip strength correlated with higher tidal volume. Two hands C-E generated the highest tidal volume of $483.78{\pm}34.14mL$, one hand O-E generated $449.59{\pm}51.09mL$ and one hand C-E generated $394.31{\pm}68.95mL$. Conclusion: Means of tidal volumes were statistically significantly different based on mask sealing methods (p<.001). Two hand C-E was performed by the two-persons task and was suggested as the most effective method. For the one-person task, one hand O-E was the more effective method compared to the previous one hand C-E.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.2
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• pp.174-182
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• 2012

In previous research, most occupant said that they have not operated ventilation system installed in the house, because of increasing of energy consumption and unconcern of ventilation. Therefore, it is necessary to applied the sensor based demand controlled ventilation for the IAQ(Indoor Air Quality) and improvement of energy efficiency in ventilation strategy. The propose of this study is to present a application method of IR(Infrared) sensor for multi-zone DCV(Demand Controlled Ventilation) in the apartment house. It is possible that IR sensor could be used for DCV, because that could detect the occupant and action. IR sensor based DCV strategies are established to evaluate characteristic of application in the apartment house and simulated by Contam program. As a result, they have some week points though, if they would be applied DCV with optimum strategy, it would be useful to improve IAQ, to reduce energy consumption.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.7
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• pp.541-548
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• 2006

A hybrid ventilation system was introduced to predict the ventilation performance of the apartments. This ventilation system was composed of the natural supply-air inlet and the forced exhaust-air outlet. Analysis was conducted by CFD technique and was performed on three ventilating flow rates; 30, 60, $120m^3/h$. As the results, residents feel comfortable thermally for $60m^3/h$. In the case of $120m^3/h$, however, residents feel uncomfortable both thermally and in air currents. In this study the energy saving for space heating is also an important factor. In the case of whole region with $180m^3/h$, residents feel comfortable at each region of the model apartment. It is shown that this hybrid ventilation system is possible method for the apartment house.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.5
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• pp.614-622
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• 2011

In this study, a new tunnel ventilation method with a high velocity air curtain flow has been investigated for improving the ventilation exhaust efficiency and removing air pollutants in subway tunnels. At upper or lower position right downstream of a main duct connected with a ventilation opening, air curtain flows were suppled into the main duct where the air flow velocity was in the range of 2~6 m/s. Exhaust efficiency was monitored for both cases with and without air curtain flow for different air velocities, locations and injection angles of the air curtain. Particulate matter concentrations (PM10, PM2.5 and PM1.0) were also checked at both the main duct and ventilation opening before and after supplying air curtain flows. Lower air velocity of the main duct flow, higher air velocity of the air curtain led to higher exhaust efficiency and the air curtain condition of 30..inclined injection toward the main flow showed the maximum exhaust efficiency. The exhaust efficiency of about 24% without the air curtain could be improved to about 34% after using the air curtain flow. PM concentration decreased at the main duct and increased at the ventilation opening after using the air curtain flow. Therefore, the suggested method to use air curtain flows in tunnels will be probably one of the promising tools to reduce air pollutants in subway tunnels.