• 한국자동차공학회논문집
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• 제22권6호
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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.

• 한국식품저장유통학회지
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• 제9권3호
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• pp.277-281
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• 2002

양파의 예건 방법 및 기간이 저장 중 부패에 미치는 영향을 구명하기 위하여 만생종인 창녕대고 품종을 이용하여 1997년~1998년의 2개년 동안 양파를 수확 후 노지 포장과조립식 간이하우스(통풍) 및 조립식 간이하우스(무통풍)에서 1~3일간 예건 후 저장하여 실험하였다. 예건 기간중의 최고기온은 무 통풍 하우스에서 가장 높았고 노지 포장에서 가장 낮았으며 특히 무통풍 하우스에서 1997년 처리 2일째 및 3일째와 1998년 처리 2일째는 41.6$^{\circ}C$이상의 고온을 경과하였다. 수확 후의 양파 수분함량은 90.3~89.5%이었으며, 예건 후에는 1997년에는 0.3~l.8%가 감소되었고, 1998년에는 0.2~2.6%가 감소되었으며, 감량정도는 노지에서 가장 많았고, 통풍하우스에서 가장 적었다. 저장기간 중 최고기온은 1997년이 평균 39.2$^{\circ}C$로서 1998년의 37.1$^{\circ}C$에 비해 높게 경과하였으며, 상대습도는 7월은 1997년에 79.3%로서 1998년의 72.7%에 비해 높았으며, 8월은 1998년이 79.1%로서 1997년의 78.2% 보다 오히려 높게 경과하였다. 처리간 부패 발생은 1997년은 저장초기에 부패가 많이 발생하였으나, 1998년은 저장 중기 이후에 부패가 많이 발생하였으며 1997년에 비해 1998년에 부패가 많이 발생하였다. 총 부패율은 통풍하우스에서 가장 낮았고 무통풍 하우스에서 가장 높았으며, 예건 기간은 길수록 부패경감 효과가 높았다. 이상의 결과를 볼 때 수확 후 저장 중 부패를 경감시키기 위해서는 통풍이 되는 하우스에서 1~2일 예건하거나 노지에서 2~3일 예건하는 것이 효과적인 것으로 판단된다.

• 한국응급구조학회지
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• 제16권2호
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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.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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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

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집B
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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.

• 한국응급구조학회지
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• 제25권3호
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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.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2006년도 추계 학술논문 발표대회 논문집
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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.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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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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• 제23권E2호
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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.

• 한국응급구조학회지
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• 제22권1호
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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.