• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.8
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• pp.1387-1395
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• 1997

Effects of the ambient air temperature and the opening position on the pattern of the clothing ventilation of a thermal manikin wearing an impermeable blouse were investigated by the trace gas method. Under an isothermal condition, the ventilation was governed by diffusion, and the ventilation rate through the wrist-openings was greatly affected by the distance from the openings. Under non-isothermal conditions, however, the ventilation was accelerated by the convection driven by the temperature gradient between the clothing microclimate and the surrounding air; the greater the temperature gradient, the greater the ventilation. Even though it was certainly affected by the ambient air temperature, the ventilation rate was more significantly influenced by the position of openings. The ventilation patterns at the arm and the body were distinctive.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.111-116
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• 2008

The objective of this paper was to show the possibility of demand-controlled ventilation (DCV) using the current Korean ventilation standard for multi-purposed facilites. Two attractive DCV approaches; $CO_2$-DCV and RFID-DCV were applied to DCV simulations for a theoretical public assembly space served by a dedicated outdoor air system (DOAS) with enthalpy recovery device. A numerical model for predicting realtime occupant number, ventilation rate, and $CO_2$ concentration under given conditions was developed using a commercial equation solver program. It was found that the current ventilation standard causes unstable ventilation system control in DCV applications, especially under $CO_2$-DCV. It is because the ventilation rate (per person) used in Korea is the sum of the outdoor air required to remove or dilute air contaminants generated by both occupant and building itself, and not a pure function of occupant numbers. Finally, it makes DCV control unstable when ventilation flow is regulated only by the number of occupants. In order for solving this problem, current Korean ventilation standard was modified as a form of ASHRAE Standard 62.1-2007 showing good applicability to various DCV approaches. It was found that this modification enhances applicability of the current ventilation standard to DCV significantly.

• Journal of Advanced Marine Engineering and Technology
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• v.29 no.7
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• pp.736-743
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• 2005

In this study, three different types of mechanical ventilation systems are compared based on their ventilation characteristics: tracer gas concentration decay characteristics, and ventilation effectiveness by calculating actual ventilation air flow rate. The experiments are performed by using a step-down method for measuring tracer gas. $CO_{2}$ gas, concentration in the model chamber. Application of a mixing factor, k, was used and measured values ranged from 0.68 to 0.77. The Type 2 ventilation system was found to have the highest ventilation effectiveness rather than the Types 1 and 3.

• Journal of the Korean Solar Energy Society
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• v.25 no.4
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• pp.133-139
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• 2005

In this paper, the ventilation performance of suspended particulates in indoor side was investigated by step-down method. Experiments were performed in function of mechanical ventilation types and locations of supply and extract air. The type 2 ventilation system shows the highest removal characteristics rather than other 2 types. It means that the displacement ventilation has also good decay rates of concentration compared to mixing ventilation.

• KIEAE Journal
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• v.16 no.6
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• pp.129-134
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• 2016

Today, natural ventilation systems are widely applied in multi-family housing. However, studies using the wind data trend line of the blower door test are insufficient. Purpose: Through this study, we will propose a computational method about ventilation performance of natural ventilation systems by conducting blower door test. Method: First, we sealed the gaps between the main systems including the natural ventilation system and conducted the blower door test. Next, the natural ventilation system was opened, the blower door test was conducted, and the difference in air flow rate between when closed and when opened was checked. Blower door test was carried out with a pressure difference of 50 Pa. Result: Therefore, the ventilation performance of the natural ventilation system was checked by drawing a trend line using the data to calculate the air flow rate at 2 Pa of the natural ventilation equipment standard pressure difference.

• Journal of Practical Agriculture & Fisheries Research
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• v.25 no.1
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• pp.14-19
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• 2023

In summer, the natural ventilation performance for varying greenhouse width is very important in the glasshouses for year round cultivation. The effect of the side openings and greenhouse width on natural ventilation performance was analyzed by simulation. The necessary ventilation rate with different solar radiation transmittance increased significantly when the outside temperature grows higher. The necessary ventilation rate of 40% transmittance was about half of that of 90% transmittance. In consequence, shading effect on temperature control in greenhouse is significant in summer. When the total area of the openings for ventilation is constant, the maximum ventilation rate happens when the area of roof openings is equal to the area of side openings. This maximum ventilation rate is about 3 times of that of the greenhouse with roof openings and without side openings. Therefore, the side openings are advantageous to improve the natural ventilation in greenhouses. As the greenhouse width increases, the influence of side openings on the ventilation rate is becoming smaller. If the natural ventilation rate of the greenhouse with roof and side openings is to become double of that of the roof openings only, the width should be narrower than 38.4m for the Venlo type and 64m for Wide span type.

• Journal of the Korea Society of Computer and Information
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• v.29 no.3
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• pp.165-171
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• 2024

This study aims to investigate the appropriate volume of artificial ventilation and success rate when Basic - emergency medical Technician administer bag valve mask(BVM) artificial ventilation to patients experiencing respiratory failure or respiratory arrest using a respiratory rate measurement device. The research was conducted from December 11th to 12th, 2023, targeting 20 Basic - emergency medical Technicians enrolled at D University. Ten participants were selected for the experimental group, receiving BVM ventilation training with the use of a respiratory rate measurement device, while the other ten were assigned to the control group, receiving BVM ventilation training without the use of a respiratory rate measurement device. The experiment involved providing artificial ventilation for 2 minutes. The results of the study indicated that the control group did not provide accurate tidal volume (p=.025). The experimental group demonstrated a higher success rate of ventilation over the 2-minute period, while the control group showed a significant difference (p=.001). Subjective perception of tidal volume and objectively measured tidal volume also exhibited a significant difference in the control group (p=.010). Therefore, training with a respiratory rate measurement device can align the subjective perception of tidal volume with objective measurements, increase the success rate of ventilation, and potentially contribute to improving survival rates in patients experiencing respiratory failure or respiratory arrest during cardiopulmonary resuscitation.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1337-1342
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• 2009

This test was progressed in the test house of KICT as sectional research of Center for Sustainable Housing. It included a ventilation rate of hybrid ventilation equipment, temperature, and gas test using the SF-6. The purpose of this test is to demonstrate the performance of viovent by estimating an outdoor air flow rate through viovent which the flimmer filter is installed and decide the leakage after operating the constant airflow fan within a house. First, the outdoor airflow rate through viovent measured $130\;m^3/h$ more than a legal required ventilation rate, $104\;m^3/h$. And then it sufficiently satisfy a legal standard, 0.7 air change/h. Secondly, the result of this test exposes that the leakage in the residence is about $20{\sim}25%$. Especially, the outdoor air flowing through the gate occupies 50% of the total leakage.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.143-146
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• 2006

There has been growing concern regarding IAQ(Indoor Air Quality) recently, and IAQ problems from the air-tightness and use of chemical materials addition to the building materials have become increasingly important factors in the built environment. Ventilation is supposed as the solution of healthy indoor quality, and Korea government requests that all new apartment buildings must have a ventilation system as a matter of duty since January, 2006. The purpose of this study is to investigate the indoor concentration change of VOCs include the Formaldehyde according to many different ventilation supply types. Results showed that the reduction effect of target pollutants by the ventilation system was very slight. The cause of these results was attribute to increase the emission rate of building materials by increasing the ventilation rate.

• KIEAE Journal
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• v.15 no.6
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• pp.81-86
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• 2015

Purpose: Condensation in the apartment housing is one of the most significant defects and complaints for condensation are rapidly increasing according to the growing interest in residential environment. Korea government established a regulation for reducing condensation in the apartment housing and TDR is adapted as a standard. However prevention of condensation depend on improving the performance of building envelop has limitation because of the increase of the cost. Centralized Hybrid ventilation system is suggested to prevent condensation. Method: Field measurement was conducted to verify the ventilation rate of the ventilation system. Based on the measurement, air network and CFD simulation was conducted to analyze ventilation rate for each room. Surface temperature was calculated by regulated TDR according to the regions and surfaces. The performance of condensation prevention was evaluated by the ventilation rate and surface temperature. Result: In the results, it was found that condensation was prevented in more than 90% of households by the centralized hybrid ventilation system which provided 0.19 ~ 0.81ACH for each room.