• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.6
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• pp.89-95
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• 2014

This study presented the benefit of the pre-ventilation using solar sunroof with integrated photovoltaic. Recent year, auto-makers make an effort to enhance the fuel efficiency and moreover to clean the cabin passenger's health. Solar energy, one of the alternative energies, adapted in automotive air handling system, in order to pre-ventilation when vehicle parked under the sun in summer. The power generated by a prototype solar sunroof has been used to run blower in a air handing system. And the solar sunroof was installed in a vehicle, and evaluated to find out benefit of the pre-ventilation. The effect of reducing the cabin temperature about $3^{\circ}C{\sim}10^{\circ}C$ with 20 ~ 40W power generator from solar sunroof were obtained in the pre-ventilation test. This reduced thermal load can lead to the reduction of air-conditioning operation time than that of current car. Moreover, fuel economy may increase as a results of the short use of the air-conditioning time. Additionally, Total Volatile Organic Compounds in the cabin is reduced maximum 80% than that of the current vehicle.

• Food Science and Preservation
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• v.9 no.3
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• pp.277-281
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• 2002

To decrease the rot of onion bulb during storage in simple house, later cultivar 'Changnyeungdaego' was dried after harvest on the field, ventilation house and non-ventilation house during 1 to 3days in 1997 and 1998. The maximum air temperature during pre-drying maintained highest in the non-ventilation house and lowest in the field, especially higher than 41.6$^{\circ}C$ at second and third day in 1997 and second day in 1998 on the non-ventilation house. Water content of onion bulbs showed 90.3∼89.5% at harvest and reduced 0.3∼l.8% in 1997, 0.2∼2.6% in 1998 after pre-drying, the rate of reduction was highest on the field and lowest on the ventilation house. Mean of maximum air temperature was 39.2$^{\circ}C$ in 1997 and 37.1$^{\circ}C$ in 1998 and relative humidity was 79.3% and 72.7% in July of 1997 and 1998, 78.2% and 79.1% in August of 1997 and 1998 during storage on the simple house after pre-drying. Rotting ratio of onion bulb showed higher in 1998 than 1997, but rotting appeared earlier 1997 than 1998. Total rotting rate as influenced by place and days of pre-drying was the lowest on the ventilation house, and highest on the non-ventilation. As the days of pre-drying increase, rotting rate of onion bulbs were lower. As above results, 1 or 2days of pre-drying on the ventilation house and 2 or 3days of pre-drying on the field were recommended to decrease the rotting onion bulb during storage.

• The Korean Journal of Emergency Medical Services
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• v.16 no.2
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• pp.75-89
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• 2012

Purpose : This research was designed to provide basic data for advanced pre-hospital airway management by comparing the time to ventilation and success rate for tracheal intubation performed with Macintosh laryngoscope and intubating Laryngeal Mask Airway(ILMA) in a manikin. Methods : All participants were novice users among EMT-Paramedic students and were divided into two groups: (1) the group for Macintosh laryngoscope guided tracheal intubation(MLG-TI) (2) the group for ILMA guided tracheal intubation(ILMA-TI). After an introductory lecture and demonstration, each group made an attempt ten tracheal intubation to compare the ventilation time and success rate for tracheal intubation. Results : 1) There was significant difference in the time to ventilation through MLG-TI, the time to first and second ventilation through ILMA-TI of the 10 attempts. 2) The time to first ventilation through ILMA-TI was significantly shorter than that of ventilation through MLG-TI. 3) There was no significant difference between the time to ventilation through MLG-TI and the time to second ventilation through ILMA-TI. 4) The success rates of ILMA-TI were significantly higher than those of MLG-TI. Conclusion : ILMA-TI can be an alternative method for MLG-TI in advanced pre-hospital airway management.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.270-275
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• 2007

Pollutants emitted by Diesel trains seriously affected on the ventilation characteristics in the subway or railway tunnel network systems. Thus, numerical prediction results and analyses are required to engineers who should design ventilation facilities. So here, this paper presents some numerical results about the ventilation characteristics, such as pollutants distributions and a suitability of the ventilation facilities pre-designed in case that diesel trains use the same railway track with normal passenger trains

• Proceedings of the KSME Conference
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• 2001.06b
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• pp.87-92
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• 2001

In automobile highway tunnels, in order to maintain a suitable environment for drivers and traffic, visibility in the tunnel must be maintained, and the concentrations of poisonous substances including carbon monoxide must be kept at or below allowable levels. For this reason, in long tunnels and tunnels with heavy traffic, ventilation facilities are installed. When the ventilation facilities are run at full capacity, the environment in the tunnel is obviously adequately maintained, but this consumes a great deal of electric power. Consequently, a central problem in highway tunnel ventilation control systems is to keep the pollution concentration at or below the allowable level, and thus provide a safe environment for traffic, while consuming as little electricity as possible. This paper introduces an operation method of longitudinal flow ventilation systems with jet-fan, dust collector and vertical ducts.

• The Korean Journal of Emergency Medical Services
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• v.25 no.3
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• pp.7-16
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• 2021

Purpose: The I-gel device is Korea's most frequently used airway management method during pre-hospital cardiopulmonary resuscitation (CPR). This study aimed to compare changes in ventilation volume according to the fixation method with a simulated manikin. Methods: We placed I-gel into an advanced life support simulator and compared tape and band fixation conditions. CPR was performed according to the 2020 Korean CPR guidelines, using a mechanical chest compression device and an adult bag. The positional shift of I-gel and the ventilation volume of the simulated manikin were measured after performing CPR for 20 minutes. Five trials were carried out in each setting. Statistical analysis was carried out with SPSS 27.0. P < .05 was considered significant. Results: Positional shift after 20 minutes of CPR was as follows: tape fixation, 7.2 ± 0.2 mm; band fixation, no change, indicating a significant difference between the two groups (p=.003). The mean ventilation volume was tape fixation, 482.63 ± 30.84 mL; band fixation, 544.96 ± 22.98 mL, showing a significant difference (p=.002). Conclusion: When using the I-gel during pre-hospital CPR, using a band-type fixing device with elasticity rather than fixing the tape provides stable and appropriate ventilation by maintaining the fixed position.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.139-142
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• 2006

The indoor air quality of new apartment buildings, which is known to cause sick housing syndrome, has become a major concern among apartment residents as well as construction companies in Korea. In this study, the effects of environmentally friendly materials and ventilation system are evaluated to compare the strategies applied to improve indoor air quality at the pre-occupancy stage. Six residential units are tested under three conditions : one unit is consisted of environmentally friendly materials and ventilation system, another unit is consisted of environmentally friendly materials and non-ventilation system, and the other four units are consisted of common materials and non-ventilation system.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.105-112
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• 2007

Recently developed raised floor heating system is not only capable of basic function to reduce noise between floors, but also is a multi-functional floor heating system enabling natural ventilation. The procedure of this system for natural ventilation is to import outdoor air through bottom space of the floor heating system, circulate indoor space and discharge it out of ceiling. In winter, powerless natural ventilation is possible with buoyancy effect caused by temperature difference between outdoor and indoor. And it also allows saving of energy by importing pre-heated air in bottom space of the floor heating system. To evaluate ventilation performance of this system, on-site measurement was conducted in 2 test laboratories, and the nominal air change rate was satisfied as 0.4$\sim$0.8 h-1 under the condition of outdoor temperature $5^{\circ}C{\sim}-5^{\circ}C$, which was evaluated as highly possible to be applied as a natural ventilation system in multi-family houses.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.E2
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• pp.66-73
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• 2007

The introduction of tracer gas techniques to ventilation studies in indoor environments provides valuable information that used to be unattainable from conventional testing environments. Data acquisition systems (DASs) containing analogue-to-digital (A/D) converters are usually used to function the key role that records signals to storage in digital format. In the testing process, there exist a number of components in the measuring equipment which may produce system-based inference to the monitored results. These unwanted fluctuations may cause significant error in data analysis, especially when non-linear algorithms are involved. In this study, a pre-processor is developed and applied to separate the unwanted fluctuations (noise or interference) in raw measurements and to reduce the uncertainty in the measurement. Moving average, notch filter, FIR (Finite Impulse Response) filters, and IIR (Infinite Impulse Response) filters are designed and applied to collect the desired information from the raw measurements. Tracer gas concentrations are monitored during leakage and ventilation tests in the model test room. The signal analysis functions are introduced to carry out the digital signal processing (DSP) work. Overall the FIR filters process the $CO_2$ measurement properly for ventilation rate and mean age of air calculations. It is found that, the Kaiser filter was the most applicable digital filter for pre-processing the tracer gas measurements. Although the IIR filters help to reduce the random noise in the data, they cause considerable changes to the filtered data, which is not desirable.

• The Korean Journal of Emergency Medical Services
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• v.22 no.1
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• pp.49-59
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• 2018

Purpose: The purpose of this study was to develop an assistant device for the promotion of bag-valve-mask ventilation based on a non-equivalent control group pre-test and post-test design. Methods: The experimental tool was a mask assistance device developed by the researchers. Data were analyzed using SPSS 21.0 with the cardiopulmonary resuscitation (CPR) evaluation program from August 18 to 30, 2016. The research tools included general, hand-related, and ventilation-related characteristics. Results: Before and after using the mask assistance device, the tidal volume increased by 64 mL (p<.001) from 461.76 mL to 525.86 mL. The tidal volume for control was 477.86 mL, and there was a statistical difference (p<.05). The ventilation frequency in device users was 10 times per minute for a total of 20 ventilations with before 10.65 after 10 times, and that of the control group was before 10.36 times after 10 times; there was no difference in both groups(p>.05). The accuracy of the assistance device was $81.72{\pm}30.86%$, which was a very high value. However, the accuracy of ventilation in the control group with no assistance device was $18.97{\pm}32.44%$, which was a very low accuracy rate. Conclusion: This study's results suggested utilizing the newly-developed mask assistance device in CPR, and showed increases in tidal volume and accuracy of ventilation using the bag-valve-mask ventilation equipment. The general and hand-related characteristics did not have any effect, so the use of the device proved to increase the efficacy in all users.