• Asian Journal of Atmospheric Environment
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• v.5 no.4
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• pp.247-262
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• 2011

This study assessed the health risks of childhood exposure to PBDEs via different possible pathways in children's facilities and indoor playgrounds. When PBDE contamination was measured, it was determined through multiple routes, including inhalation of indoor dust, dermal contact with product surfaces and children's hands, and incidental dust ingestion. Samples were collected from various children's facilities (playrooms, daycare centers, kindergartens, and indoor playgrounds) during summer (Jul-Sep, 2007) and winter (Jan-Feb, 2008). The hazard index (HI) was estimated for non-carcinogens, and PBDEs, such as TeBDE, PeBDE, HxBDE, and DeBDE, were examined. The sensitivity to the compounds did not exceed 1.0 (HI) for any of the subjects in any facility. However, current data about toxicity does not reflect effects that were fully sensitive in children, so there is uncertainty in the dose-response data. The contribution rates of PBDEs were 71.4 to 96.1% and 3.7 to 28.2% for intake and inhalation exposure, respectively, indicating that intake of floor dust and inhalation are the primary routes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.443-449
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• 2017

The imbalance of air supply and the exhaust on subway platforms has led to the installation of platform screen doors in underground subway stations. This imbalance causes the accumulation of pollutants on the platform and loss of comfort due to the lack of ventilation. In this study, a floor exhaust system was optimized using computational fluid dynamics (CFD) and an optimization program. The optimized floor exhaust system was manufactured and tested experimentally to evaluate the particle collection efficiency. CFX 17.0 and HEEDS were used to analyze the flow field and optimize the principal dimensions of the exhaust system. As a result of the three-step optimization, the optimized floor exhaust system had a total height of 1.78 m, pressure drop of 430 Pa, and particle collection capability of 61%. A fine dust particle collection experiment was conducted using a floor exhaust system that was manufactured at full scale based on the optimized design. The experiment indicated about 65% particle collection efficiency. Therefore, the optimized design can be applied to subway platforms to draw in exhaust air and remove particulate matter at the same time.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.769-772
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• 2011

We propose a sweeping machine is equipped with a polyester filter to retain small particles of dust. The filter is washable and can be easily removed for maintenance purpose or eventual replacement. Research continues into key areas such as making the structure of machine as ship' s floor grinder as possible, and designing algorithms and systems for efficiency-related system technologies.

• Korean Journal of Poultry Science
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• v.40 no.3
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• pp.253-262
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• 2013

This experiment was conducted to investigate the effects of floor type and heating system on performance, housing environment and health status of ducks reared in three types of duck house (OD : Open floor house-Direct heating system, OF : Open floor house-Floor heating system and LD : Loft type house-Direct heating system). In OF treatment, PVC pipes were installed for heating under concrete floor and covered with litter. In LD treatment, plastic mesh was installed 50 cm above the floor so that duck's droppings can pass through it. Each treatment had four replicates of 25 birds (Cherry Valley duck breed) per pen. There were no significant differences in weight gain and feed intake of ducks for 6 weeks among all treatments. However, feed conversion ratio in LD was significantly higher (p<0.05) than that in OF. No differences were found in carcass charac- teristics, with the exception of abdominal fat weight where OF were higher than the others. Concentrations of $CO_2$ and $NH_3$ gas in OD were higher than those of OF and LD at 3, 4 and 5 weeks. Moisture content in litter of OF was lower than that of OD. In contrast, the amount of dust in the air was higher in OF than in OD. The amount of fuel used for 6 weeks in LD was lower about 21% than that in OD. Some of unusual symptoms were observed in open floor house and loft type house, such as lying, spraddle legged, twisted ankle and legs, wounded sole, or etc. No components of leukocyte and erythrocyte of blood were significantly different among all treatments. The results of this experiment showed that OF and LD systems had no positive effects on performance of meat type commercial duck. However, there were some positive effects of certain house type for the improvement of environmental condition in duck house for hygienic production. In the future, more research on the effect of various facilities and systems for duck house is needed.

• Journal of Korean Public Health Nursing
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• v.10 no.2
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• pp.51-60
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• 1996

This study was conducted to provide basic knowledges of effective environmental control of patients with allergic rhinitis. From July to October 1995, 58 dust samples Were drawn from the bedrooms of patients with allergic rhinitis who were registerd at an allergy clinic of a hospital. Those samples were examined for the amount of house mite allergens & dusts. The data were analysed by using ANOVA and Pearson correiation coefficients. The results were as follows : 1. As for the amount of house mite allergens in terms of environmental factors, the amount of house mite allergens of using washing water temperature of bedding above than $55^{\circ}C$ was significantly lower than that of below $54^{\circ}C$. Other environmental factors such as type of house, area of bed room floor, bed in bedroom, bedroom cleaning by vacuum cleaner, days after bedding washing, relative humidity of bedroom were relate to the amount of house mite allergens. 2. As for the amount of dusts in terms of environmental factors, the amount of dusts of days of days after bedding washing more than 15 days was significantly lower than thant of less than 15days. Other environmental factors such as type of house, area of bedroom floor, bed in bedroom, bedroom cleaning by vacuum cleaner, was hing water taemperature of bedding, relative humidity of bedroom were not relate to the amount of dusts. 3. There was a significant positive correlation between the amount of house mite allergens and the amount of dusts. It may be conclusively said. the amount of dusts and house mite allergens were closely associated with the washing temperature and days after washing of bedding. Hence. intensive instruction for the methods of bedding washing was needs of the patients with allergic rhinitis.

• KIEAE Journal
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• v.11 no.1
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• pp.3-8
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• 2011

Sound absorbing materials used for lightweight panels and interior material are mainly made of fibroid material such as glass wool or rock wool. However these fiber type sound absorbing materials have some problems such that sound absorption could be decreased as time goes by because of durability. In addition, dust scattering from fiber type material can cause another problem in health. In this point of view, this study aims to develop environment friendly sound absorbing material using Hwangto(so called loess or yellow soil), a traditional housing material. Hwangto is natural housing material in Korea and generally known for improving indoor air quality. Hwangto panel is made to construct on the floor, wall and ceiling, and expected that there is not enough absorption. Present study tried to develop environment friendly sound absorbing material that has high sound absorption performance with good environment performance in terms of air quality. Pore rate was designed to maximize the absorption in the specific frequency bands, and two kinds of backing space were applied in order to see the effect of backing space. As a result peak frequency that has maximum absorption is going high as the pore rate is increased. The backing space provides more absorption and makes the peak frequency down to low.

• Journal of Korean Society of Forest Science
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• v.94 no.2 s.159
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• pp.96-102
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• 2005

This study evaluated the chemical characteristics of rainfall and throughfall in Pinus koraiensis and Larix leptolepis forests. We analyzed pH, EC, and concentrations of cations and anions in rainfall, throughfall and stemflow collected from both forest types in the experimental forests of the central Korea. The concentrations of chemical elements were much higher in throughfall and stemflow than in rainfall for both forest types, and were significantly different among the seasons. Comparing the chemical elements between the P. koraiensis and L. leptolepis plantations, there were not significantly differences in throughfall, but the concentrations of almost elements of stemflow in P. koraiensis were almost lower than those in L. leptolepis. For seasonal inputs to the forest floor, more than half of the total input of $Ca^{2+}$, ${NO_3}^-$and ${SO_4}^{2-}$ was observed in spring. This suggests that air pollutants such as NOx and SOx accompanying calcium-rich aeolian Yellow Sand (Asian dust) from China could have an important influence on nutrient cycles in Korean forests.

• Journal of the Korean Institute of Rural Architecture
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• v.16 no.1
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• pp.17-26
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• 2014

This study examined the trend of floor space characteristics, size characteristics and modeling characteristics so as to evaluate the satisfactory level of subjects living in Hanok. By doing so, the type of Hanok was classified into 5 groups. The satisfactory level was evaluated after the subjects resided in Hanok based on each type of housing. In the satisfactory level investigation, which was conducted after the residence, the overall satisfactory level on Hanok showed to be high. In the evaluation on the residence scale, positive results were generally achieved regarding 'full size of residence', 'number of rooms compared to residence size', 'size of living room', etc. The indoor environment of residence evaluation mainly showed positive results regarding 'ventilation', but most subjects were unsatisfied in regard to 'heating', 'noise', 'lighting', etc. In the behavioral factor evaluation of residents, positive results were gained regarding 'health', but comparatively negative results showed based on items of 'construction expense', 'burden of maintenance expense', 'investment value', etc. After analyzing the influential factors on the overall satisfactory level, results showed that 'dust inflow' of the physical site environment evaluation, 'size of living room' of the residence size evaluation, 'heating' of the residence indoor environment evaluation, and 'burden of maintenance expense' in the behavioral factor evaluation significantly influences the overall satisfactory level.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.147-148
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• 2023

Steel doors, which are common in general buildings, do not seal the gap between the door and the floor, so drafts, noise, dust, and lights flow from the outside, and shielding devices are installed in various materials and methods, such as adding magnetic gate paper to the side of the door or installing a gasket under the door, but performance is limited. Accordingly, in order to fundamentally solve these problems, we researched and developed a double gap blocking device that can improve fire resistance and airtightness performance in steel doors. Unlike general products, the double gap blocking device has the advantage of maximizing airtight performance by forming an air layer in the center when the door is closed, as well as greatly improving the fire resistance performance, which is the basic performance of the fire door.

• Journal of Families and Better Life
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• v.24 no.1 s.79
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• pp.159-179
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• 2006

Each ethnic group has different cultural backgrounds and each culture has developed with its own traditions. The interaction between different cultures is getting more active through acculturation and cultural contacts. The purpose of this study was to compare domestic living of Korean immigrants with Australians in the form of a Cross-Cultural study. For this, usage of domestic space and seating style of 52 Korean households and 53 Australian households in Melbourne were analyzed. Ethnographic research with questionnaire was used. The results of the research were as follows. 1. The most popular type of Living-Dining-Kitchen arrangement was L+ K. D for Koreans and L. D . K for Australians. 2. A laundry room was indispensable for both and they all wanted to do ironing in there as well as dry. Both were satisfied with the type which toilet was separated from the bathroom Drain hole on the floor of the bathroom was not indispensable for most Koreans and Australians. 3. Koreans and Australians were doing various activities in living area and both were getting together around kitchen(dining) area. The particular thing of Koreans was that they were using the main bedroom with multiple purpose. 4. The seating style of Koreans and Australians belong to chair-seating style generally. But Koreans were using floor seating style in making bed for the guest and making Kimchi. Koreans and Australians were using mixed style of floor seating and chair-seating in relaxing time with watching TV, treating guest or so. 5. Koreans were not satisfied with using carpet cause of dust but Australians were satisfied with the carpet cause of warmness. 6. Most Koreans and Australians were take off shoes inside of the house. Koreans were organize shoes around the front door of the house usually and Australians were organize shoes in bedroom usually. 7. The most popular heating system was ducted heating for both. The level of satisfaction about ducted heating was low for Koreans because they though that it could contaminate air. Australians were satisfied with ducted heating because they though that this one was fit on the weather of this area. 8. Living room was the most important one for Koreans and Australians and they also thought it should be decorated well for entertaining guests. Most Koreans were estimate that the brightness of the light of the house was not enough but it was estimated to moderate for Australians on the contrary.