• Journal of Korean Society for Atmospheric Environment
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• v.24 no.2
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• pp.153-161
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• 2008

The guidelines for indoor air quality of public transportations such as subway, train and bus was presented by Korean Ministry of Environment last end of year 2006 based on the great consequence of indoor air quality in daily life. Two main parameters, carbon dioxide($CO_2$) and particulate matters smaller than $10\;{\mu}m(PM_{10})$, were selected as index pollutants for the management of indoor air quality. The former pollutant, $CO_2$, is regarded as index of ventilation status and the major source of $CO_2$ in the train or subway is the exhalation of passengers. It is publically perceived that the high $CO_2$ concentration in a crowded subway will be reduced and ventilated with outdoor air by door-opening taken every 2 or 3 minutes when the train stops each station. However, there has not been any scientific proof and quantitative information on the effect of door-opening on the $CO_2$ reduction by ventilation with outdoor air. In this study, $CO_2$ concentration and number of passengers were measured at each station on the 3 lines of Korail metropolitan subway. In order to evaluate the effect of $CO_2$ reduction by door opening, the theoretical approach using the $CO_2$ balance equation was performed. By comparing the predicted data with monitoring one, the optimum $CO_2$ dilution factor was determined. For the first time, it was quantified that about 35% of $CO_2$ concentration in the subway indoor was removed by the door-opening at each station.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.330-332
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• 2003

In this paper, It is introduced new sound quality method, FI(Fluctuation Index) and the example applied Outdoors side Air-conditioner noise evaluation. Because FI is applied with very simple algebraic calculation algorithm, it can be applied some other application without spending high time and cost.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.2
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• pp.607-611
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• 2015

Background: Chronic respiratory disease is an important factor for development of lung cancer. To explore the influence of hazy weather on respiratory diseases and its variation the present study was conducted. Materials and Methods: Data from air pollution surveillance from January to October 2014 and case records of visiting patients in the $263^{th}$ Hospital of Chinese PLA in the corresponding period were collected to analyze the relevance between different degrees of air pollution (hazy weather) and the number of visiting patients in Department of Respiratory Disease. Results: Air quality index (AQI) of hazy weather had significantly positive association with particulate matter 2.5 ($PM_{2.5}$) and the number of patients with 5 kinds of respiratory diseases i and different pollutants had distinct influences on various respiratory diseases. Conclusions: The degree of air pollution in Beijing City is in close association with the number of patients with respiratory diseases, in which $PM_{2.5}$ and $SO_2$ are in more significant influences on all respiratory diseases. This could have essential implications for lung cancer development in China.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.1
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• pp.75-82
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• 2000

This paper presents the predicted results by CFD technique of air flow and contaminant distribution in a full-scale kitchen opened to a living room, ventilated by a exhaust hood. To analyze the characteristics of the indoor environment, the concept of contaminant index was defined. In this study, the locations of the gas range and the window were chosen as the parameters to investigate the indoor environment. The values of the contaminant index for several layout of the gas range and the window were calculated and compared. When the gas range is installed along the wall with specified window location, its position in relation to the wall has unnoticed effect on contaminant infer. Once the location of the gas range is fixed, the indoor air quality may deteriorate by the proximity of the window to the gas range. This is due to the shorter distance that external fresh air must travel within the kitchen before it reaches the exhaust fan.

• Air Cleaning Technology
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• v.22 no.2
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• pp.40-49
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• 2009

Aluminum thin plate coated with epoxy resin containing about 20wt% brass powder, was applied to fins of heat exchanger. We carried out a series of detailed examinations to evaluate the anti-bacterial performance of the plate and heat exchanger (fan coil unit). In the presence of water or moisture, copper ions which have an anti-bacterial ability eluted from brass powder and showed sufficient effects on many kinds of bacteria. We also evaluated the anti-bacterial performance quantitatively by use of the index API (Anti-bacterial Performance Index) which has already been proposed by authors.

• Atmosphere
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• v.30 no.4
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• pp.439-454
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• 2020

This study investigates the change in the fine particulate matter (PM2.5) concentration and World Health Organization (WHO) air quality index (AQI) in East Asia (EA) under Shared Socioeconomic Pathways (SSPs). AQI is an indicator of increasing levels about health concern, divided into six categories based on PM2.5 annual concentrations. Here, we utilized the ensemble results of UKESM1, the climate model operated in Met Office, UK, for the analysis of long-term variation during the historical (1950~2014) and future (2015~2100) period. The results show that the spatial distributions of simulated PM2.5 concentrations in present-day (1995~2014) are comparable to observations. It is found that most regions in EA exceeded the WHO air quality guideline except for Japan, Mongolia regions, and the far seas during the historical period. In future scenarios containing strong air quality (SSP1-2.6, SSP5-8.5) and medium air quality (SSP2-4.5) controls, PM2.5 concentrations are substantially reduced, resulting in significant improvement in AQI until the mid-21st century. On the other hand, the mild air pollution controls in SSP3-7.0 tend to lead poor AQI in China and Korea. This study also examines impact of increased in PM2.5 concentrations on downward shortwave energy at the surface. As a result, strong air pollution controls can improve air quality through reduced PM2.5 concentrations, but lead to an additional warming in both the near and mid-term future climate over EA.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.10a
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• pp.371-372
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• 2008

• Korean journal of aerospace and environmental medicine
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• v.31 no.2
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• pp.38-44
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• 2021

Purpose: This study aimed to identify the prevalence of fatigue and its associated factors leading to the fatigue among Korean commercial airline pilots. Methods: An anonymous, web-based questionnaire collecting data on sleep related characteristics was completed by airline pilots. The final 1,029 samples of completed questionnaires were analyzed. The association of the risk factors with fatigue was determined using logistic regression analysis. Results: The prevalence of fatigue was 60% (Fatigue Severity Scale index≥3.2), disturbed sleep 28% (Pittsburgh Sleep Quality Index≥9), daytime sleepiness 17% (Epworth Sleepiness Scale≥10), and sleep apnea (Berlin Questionnaire≥2) 11%. The fully adjusted logistic regression showed that quality of life (odds ratio [OR]=0.16, confidence interval [CI]=0.11-0.24), daytime sleepiness (OR=1.26, CI=1.18-1.34), sleep quality (OR=1.44, CI=1.29-1.61), mental workload (OR=1.10, CI=1.05-1.14), vigorous physical activity (OR=0.82, CI=0.72-0.92), late starts (OR=1.25, CI=1.06-1.46) and average weekly flying hours (OR=1.02, CI=1.00-1.03) were associated with higher levels of fatigue. Conclusion: Lower quality of life, disturbed sleep, more subjective sleepiness, shorter sleep duration, higher mental workload, less vigorous physical activity, frequent late starts, and longer flying hour were shown to be risk factors for fatigue in airline pilots. These findings should be taken into account in the development of sleep and fatigue countermeasures for airline pilots.

• Journal of the Economic Geographical Society of Korea
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• v.14 no.2
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• pp.143-156
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• 2011

Recently, the environmental problems become a serious social issue, there are many efforts to manage it efficiently. As one of the ways to measure the environment in quantitative index, the environmental indicators are used in decision-making process. Air Environmental Index(AEI), which is derived from the U.S. Air Quality Index(AQI), illustrates the degree of air pollution. In study as follows: to find the charateristics of administrative dongs in Seoul, correlation analysis is conducted based on the land-use patterns and daily traffic data that represent AEI and urban spatial structure of Seoul.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.4
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• pp.413-427
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• 2006

It is necessary to study and develop guidelines for providing comfort and health indoor air quality for office workers since air-tight envelope system of current office building may cause poor indoor air quality. The purpose of this study is to propose guideline for volatile organic compounds in office base on the field study, human health risk assessment and cost-benefit analysis. The field study was conducted to survey the concentrations of volatile organic compounds in indoor air of 69 offices from June to September, 2005 in Seoul and Gyeonggi-do. The rate of excess to guideline of volatile organic compounds in indoor air of new apartment on the Ministry of Environment in Korea(MOE) was surveyed 37.6% for benzene, 6.8% for toluene, and 1.5% for ethylbenzene. As the result of human health risk assessment, mean cancer risk did not exceed 10-6 which is guideline of US.EPA. Also, total hazard index did not exceed 1 which is guideline of US.EPA. Through the cost-benefit analysis of angle on the social-economics to verify the necessary to establish the standards of volatile organic compounds for improvement and development of indoor air quality in office, the present value of benefit was higher than the present value of cost. With the above considerations in mind, it is suggested that the field study for indoor air quality in offices should be expanded and human health risk assessment and cost-benefit analysis be performed th offer scientific data for decision-making of policy for improvement and management of indoor air quality in office.