• Journal of Environmental Science International
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• v.19 no.2
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• pp.125-136
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• 2010

The most important factors relating to the indoor air environment are temperature, airflow, humidity, and contaminant concentration. A sensitivity analysis of indoor environment factors was carried out to grasp influences along with changes of atmospheric conditions. An integrated multizone model was used to predict these sensitivities. This model was applied to an apartment with six zones. Airflow rates are influenced very seriously by changes of wind direct or wind velocity, but are influenced very slightly by changes of outdoor air temperature and are not influenced at all by changes of outdoor air humidity or contaminant concentration. Indoor air temperatures are influenced very directly by changes of outdoor air temperature, but are influenced very slightly by wind direction or wind velocity and are not influenced at all by changes of outdoor air humidity or contaminant concentration. Indoor air humidities are influenced very directly by changes of outdoor air humidity, but are not influenced at all by changes of outdoor air contaminant concentration and have little or no influence by changes of wind direction, wind velocity, or outdoor air temperature. Indoor air contaminant concentrations are influenced very seriously by changes of wind direct or wind velocity, but are influenced somewhat by changes of outdoor air contaminant concentration and are influenced very slightly by changes of outdoor air temperature and are not influenced at all by changes of outdoor air humidity.

• Journal of Environmental Health Sciences
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• v.34 no.5
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• pp.361-368
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• 2008

Objective to assess whether exposure to air pollutants is associated with postneonatal infant death, using a timeseries methodology, between 1999 and 2003 in Seoul, Korea.. Methods We investigated the short-term effects of air pollution for 548,725 live births during the study period. The daily count of postneonatal infant deaths from all causes and from SIDS (sudden infant death syndrome) by birth order was analyzed by a Generalized Additive Poisson model, with controlling for the effects of seasonal trends, air temperature, relative humidity, barometric pressure, and day of the week as covariates. Results During the study period, we observed 699 deaths from all causes and 47 deaths from SIDS. We did not find any significant associations between daily mortality and ambient levels of air pollutants except for CO and $NO_2$. The estimated relative risk of postneonatal infant death from all causes was 1.17 (95% CI=1.04-1.32) and 1.16 (95% CI=1.03-1.29) by IQR (interquartile range) for CO and $NO_2$ respectively. Also, we observed no clear trend of the mortality effects of air pollution by birth orders. Conclusion In conclusion, our findings suggest that air pollution, in general, influenced adversely postneonatal infant death from all-cause and SIDS although it was not statistically significant. This study may support that the rationale.

• Journal of Preventive Medicine and Public Health
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• v.45 no.5
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• pp.309-315
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• 2012

Objectives: Changes in air temperature and its relation to ambulance transports due to heat stroke in all 47 prefectures, in Japan were evaluated. Methods: Data on air temperature were obtained from the Japanese Meteorological Agency. Data on ambulance transports due to heat stroke was directly obtained from the Fire and Disaster Management Agency, Japan. We also used the number of deaths due to heat stroke from the Ministry of Health, Labour and Welfare, Japan, and population data from the Ministry of Internal Affairs and Communications. Chronological changes in parameters of air temperature were analyzed. In addition, the relation between air temperature and ambulance transports due to heat stroke in August 2010 was also evaluated by using an ecological study. Results: Positive and significant changes in the parameters of air temperature that is, the mean air temperature, mean of the highest air temperature, and mean of the lowest air temperature were noted in all 47 prefectures. In addition, changes in air temperature were accelerated when adjusted for observation years. Ambulance transports due to heat stroke was significantly correlated with air temperature in the ecological study. The highest air temperature was significantly linked to ambulance transports due to heat stroke, especially in elderly subjects. Conclusions: Global warming was demonstrated in all 47 prefectures in Japan. In addition, the higher air temperature was closely associated with higher ambulance transports due to heat stroke in Japan.

• Journal of Environmental Health Sciences
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• v.26 no.2
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• pp.80-90
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• 2000

To determine the effect of air pollutants in Taejon City, we used medical insurance claim data for asthma and the data monitored from telemetry system of Ministry of Environment for air pollutants and meteorological factors. From November 1st, 1997 to October 31th, 1998, 95,629 asthma patients were covered by medical insurance at Taejon City. Subjects were composed of 49,563 males (51.8%) and 46.336 females(48.2%), and among the subjects, the proportion under 15 years old was 62.8% of the total. During the study period, daily mean concentrations of each air pollutants-So2, No2, CO, O3 and TSP-were 9.8 ppb, 17.6 ppm, 1.414 pp, 17.3 ppb and 60.6 $\mu\textrm{g}$/㎥, respectively, which were lower than each of the environmental recommended exposure levels, Through the simple correlation analysis between each air pollutants and meteorological factors, O3 was positively correlated with temperature, but negatively with relative humidity. TSP, SO2, NO2, CO were negatively correlated with meteorological factors, and these air pollutants except O3 were positively correlated with each other, O3 was correlated with TSP positively but the others negatively. Estimating relative risks of each air pollutant with the baseline general additive model, daily mean concentrations of TSP(Lag 0, 1, 4, 5day) were significantly associated with the increase of the asthma admission. Two age subgroups, under 15 and 15~54 have shown various association of all air pollutants concentration with the asthma admission. However, in case of over 54 age subgroup, only TSP(Lag 0 day) among all air pollutants was associated with the asthma admission. Each of ambient outdoor pollutant concentrations in Taejon City are significantly associated with the admission of asthma patients even though all concentrations in Taejon City are significantly associated with the admission of asthma patients even though all concentrations were much lower than the environmental recommended exposure levels. Therefore, continuous effort lowering air pollutant concentration and introducing an active environmental conservation policy should be implanted for preventing hazardous health effects. Considering major proportion of asthma admissions, high susceptibility and less confounding factors among the age subgroup under 15 will be a useful target population for assessing such health effect monitoring.

• The Journal of Information Systems
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• v.8 no.2
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• pp.145-168
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• 1999

There are still occurring aviation accidents in spite of great preventing efforts all over the world. This paper contains some methods to prevent aircrafts deficiencies and accidents. First part of this paper refers to the background of those aviation deficiencies on mechanical, human and environment structures which influence directly to the air accidents and general survey on various theories of the aircraft's systems. On the way we discussed the general situations of the air tool's deficiencies which cause tragic accidents to the human lives and assets. After analysis on the situations we suggest the new systems which would forecast more detail accuracies concerned air elements for the safety flying. Then we introduce the following new systems resulting from the forecasting which can solve problems on aircraft deficiencies and complex interrelationships among air accidental factors. To simplify the complex systems, we needed to build the mechanical and organizational database for maintaining the procedures of the past troubleshooting on the major parts preventing deficiencies of those mechanical units. These suggested systems will contribute a great deal of aids, the maintenance credibility and air safety for the air operations and all customers in the world. Avoiding the past troubleshooting from just by using simple systems which can forecast main causes of the units and parts of the crafts, this system will be able to provide excellent management tools for the promoting aviational industries. The comfortable and convenient air operations are very valuable works, and the scientific method and detail maintenance will improve our daily air life by minimizing accidents. Adapting these developing systems, for the forecasting aircraft deficiencies and accidents can be integrated with the other aircraft management systems to promote more air safety in the world. This study is focused to eliminating aircraft accidents through forecasting deficiency symptom procedures by relational coordinations among all of the systems. Futhermore we need continuously detailed analysis and study for eliminating air accidents all together those who work in those fields.

• Asian Journal of Atmospheric Environment
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• v.9 no.2
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• pp.101-113
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• 2015

Air quality index (AQI) or air pollution index (API) is commonly used to report the level of severity of air pollution to public. A number of methods were developed in the past by various researchers/environmental agencies for determination of AQI or API but there is no universally accepted method exists, which is appropriate for all situations. Different method uses different aggregation function in calculating AQI or API and also considers different types and numbers of pollutants. The intended uses of AQI or API are to identify the poor air quality zones and public reporting for severity of exposure of poor air quality. Most of the AQI or API indices can be broadly classify as single pollutant index or multi-pollutant index with different aggregation method. Every indexing method has its own characteristic strengths and weaknesses that affect its suitability for particular applications. This paper attempt to present a review of all the major air quality indices developed worldwide.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.6
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• pp.182-193
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• 2000

Several metrics have been used in crash discrimination algorithms in order to have timely air bag deployment during all frontal crash modes. However, it is still challengine to have timely air bag deployment especially during the oblique, the pole and the underride crash mode. Therefore, in this paper a new crash discrimination algorithm was proposed, using the absolute value of the deceleration change multiplied by the velocity change as a metric, and processing the metric as a function of the velocity change. The new algorithm was applied for all frontal crash modes of a minivan and a sports utility vehicle, and it resulted in timely air bag deployment for all frontal crash modes including the oblique, the pole and the underride crash mode. Moreover, it was proposed that an accelerometer be installed at each side of the rails, rockers or pillars to assess the crash severity of each side and to deploy the frontal air bags at different time especially during an asymmetric crash such as an oblique and an offset crash. As an example, the deceleration pulses measured at the left and right B-pillar·rocker locations were processed through the new algorithm, and faster time-to-fires were obtained for the air bag at the struck side for the air bag at the other side.

• Korean Architects
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• v.3 no.7 s.7
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• pp.21-29
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• 1968

It is axiomatic that all living things on the earth's surface are enveloped by an ocean of air at all times. An architecture meant to serve these creatures must naturally take into account problems posed by the currents in this ocean of air. Because air space is necessary to human life, it is a central concern of good architecture. In studying how to manipulate these spaces architecturally to best advantage, problems concerning the fluctuation of air currents should be a primary concern.

• Computers and Concrete
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• v.20 no.2
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• pp.165-176
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• 2017

Textile Reinforced Cementitious Composite (TRCC) became the most common construction material lately and have excellent properties. TRCC can be employed in the manufacture of thin-walled facade elements, load-bearing integrated formwork, tunnel linings or in the strengthening of existing structures. These composite materials are a combination of matrix and textile materials. There isn't much research done about the usage of polymer modified matrices in textile reinforced cementitious composites. In this study, matrix materials named as fine grained concretes ($d_{max}{\leq}1.0mm$) were investigated. Air entraining effect of polymer modifiers were analyzed and air void content of fine grained concretes were identified with different methods. Aim of this research is to study the effect of polymer modification on the air content of fine grained concretes and the role of defoamer in controlling it. Polymer modifiers caused excessive air entrainment in all mixtures and defoamer material successfully lowered down the air content in all mixtures. Latex polymer modified mixtures had higher air content than redispersible powder modified ones. Air void analysis test was performed on selected mixtures. Air void parameters were compared with the values taken from air content meter. Close results were obtained with tests and air void analysis test found to be useful and applicable to fine grained concretes. Air void content in polymer modified matrix material used in TRCC found significant because of affecting mechanical and permeability parameters directly.

• Journal of Environmental Health Sciences
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• v.38 no.3
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• pp.184-194
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• 2012

Objectives: We investigated the effects of air pollution on allergic diseases (allergic rhinitis, asthma, atopic dermatitis) in metropolitan cities in Korea, adjusting for meteorological factors. Methods: Data on daily hospital visits and hospital admissions for 2003-2010 was obtained from the National Health Insurance Cooperation. Meteorological data was obtained from the Korea Meteorological Administration. We then calculated daily mean temperature, daily mean humidity, daily mean air pressure at sea level, and diurnal temperature range. We used data on air pollution provided by the National Institute of Environmental Research. Maximum daily eight-hour average ozone concentrations and the daily mean $PM_{10}$ were used. We estimated excess risk and 95% confidence interval for the increasing interquatile range (IQR) of each air pollutant using Generalized Additive Models (GAM) that appropriate for time series analysis. Results: In this study, we observed an association between ozone and hospital visits for allergic rhinitis, asthma, and atopic dermatitis in all metropolitan cities, adjusting for temperature, humidity, air pressure at sea level, diurnal temperature range, and day of the week. Ozone was associated with hospital visits for allergic rhinitis, asthma, and atopic dermatitis across all metropolitan cities. However $PM_{10}$ was associated with allergic-related diseases in only select cities. Also, ozone and $PM_{10}$ were associated with hospital admission for asthma in all cities except Gwangju. Hospitalization for the other diseases failed to show consistent association with air pollutants. Conclusion: In the findings of this study, there was a significant association between air pollutants and allergic-related diseases. More detailed research subdivided age group or conducting meta-analyses combining data of all cities is required.