• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2001.10a
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• pp.181-184
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• 2001

This study is performed to examine the development of the plantable concrete using excellent soil compound, crushed stone, stone dust and superplasticizer. The following conclusions are drawn ; The void ratio is in the range of $25.10{\sim}31.40%$ and the compressive strength is in the range of $69{\sim}113kgf/cm^{2}$ at the curing age 28days, respectively. The plant length was showed higher block by 10% stone dust than 20%.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.477-478
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• 2010

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.1757-1763
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• 2011

In recent years, accordance to industrial development project on railway investment, adverse environmental issues of the investment, such as disputed cases about recycling and usage of Ballast Cleaner excavated soil, have been continuously increasing. It will not only enhance the regulation of soil contamination but take considerable time and cost in future. In this study, we investigated soil contamination and burnability with soil of Chungang Line, Taebaek Line, Chungbuk Line, in order to seize a possibility of recycling Ballast Cleaner excavated soil for the natural materials and substantial heat sources, which are necessary resources for cement manufacturing process. As a result of this study, It is found that Ballast Cleaner excavated soil is satisfied with a standard. The excavated soil contains a lot of cement ingredients and fossil fuel dust incurred from freight transportation, so it is expected to use for ingredients of cement and replacement of heat sources.

• Korean Journal of Agricultural Science
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• v.40 no.3
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• pp.203-208
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• 2013

Differences in the filling amount of substrates in container can influence severely on the soil physical properties and crop growth. This research was conducted to secure the fundamental informations related to the changes in soil physical properties as influenced by the filling amount of coir dust-based substrates in container. For the experiment, three substrates were formulated by blending coir dust (CD) with expanded rice hull (CD+ERH, 8:2, v/v), carbonized rice hull (CD+CRH, 6:4, v/v) or ground and aged pine bark (CD+GAPB, 8:2, v/v). Based on the optimum bulk density, the amount of substrates filled in 347.5mL aluminum cylinder were adjusted to 90, 100, 110, 120, and 130%. Then the changes in total porosity (TP), container capacity (CC), and air-filled porosity (AFP) by various filling amounts were measured. The TP decreased linearly in CD+ERH and CD+GAPB and quadratically in CD+CRH as the filling amounts of the media increased from 90% to 130%. The CC in CD+ERH and CD+GAPB media increased as the filling amount increased from 90% to 120%, then decreased in 130%, showing quadratic change. The CC in CD+CRH was the highest in 90% filling amount and decreased gradually as the filling amount of root medea increased. The AFPs in CD+ERH and CD+GAPB media were 38 and 37%, respectively in 90% filling amount and they decreased drastically until 110% filling, then gradually in 120 and 130% filling amount showing the quadratic changes. The AFP of CD+CRH at 90% filling amount was 22% and it decreased as the filling amount increased until 130%, showing linear change. These results indicate that the increase in filling amount of substrates influenced more severely the AFP than CC, and careful consideration on container filling is required to provide a better root condition thus maximize crop growth.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.189-190
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• 2020

The importance of indoor air quality management has recently been highlighted due to environmental problems such as indoor air pollution. Among indoor air pollutants, carbon dioxide occurs in cooking, heating, burning, and causes forgetfulness, dementia and amnesia. Radon, which occurs in building materials, soil and ground, is a type 1 carcinogen that causes lung cancer in the body through breathing. These substances can be released from the room through ventilation, but there is a limit to reducing the amount of indoor activity due to reduced ventilation conditions due to increased indoor activity time. However, these substances can be removed from the gas by adsorption. The purpose of this study was to identify the properties of granular active and powdered active white soil and mix them to make cement-based active white soil adsorbent matrix for carbon dioxide, fine dust and radon gas adsorption, and to evaluate indoor air improvements according to the mixing scale. The results of the experiment showed that active carbon dioxide adsorption performance increased for carbon dioxide and radon as the exchange rate increased through physical adsorption. In particular, the higher the replacement rate of the granular active bag, the better adsorption performance was shown.

• The Journal of the Petrological Society of Korea
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• v.17 no.1
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• pp.44-50
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• 2008

A geochemical technique based on rare earth element geochemistry was used to clarity the source of the Asian dust (Yellow sand) in the Daejeon area. The Asian dusts were collected 4 times during 31th March- 2nd April and 25th May-27th May 2007. The Yellow sand shows PAAS (Post Archean Australian Shale)-normalized REE pattern of the flattened LREE and slightly depleted LREE without Eu anomaly, whereas the Daejeon soil has slightly enriched LREE and depleted HREE with negative Eu anomaly. Our results show that REE patterns of the Asian dust are LREE-flattened similar to those of the sediment from the south-eastern part of Ordos desert. This suggests that Asian dust in the Daejeon area might be derived from the south-eastern part of Ordos desert.

• Journal of Environmental Science International
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• v.29 no.1
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• pp.55-68
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• 2020

The purpose of this study is to investigate the relationship of fine dust PM₁₀ and heavy metals in PM₁₀ in Asian dust flowing into Gwangju from 2013 to 2018. The migration pathways of Asian dust was analyzed by backward trajectory analysis using HYSPLIT (Hybrid Single Particle Lagrangian Integrated Trajectory) model, and the change of heavy metal concentration and heavy metal content per 1 ㎍/㎥ of fine dust PM₁₀ in Gwangju area were analyzed. Also, the characteristics of the heavy metals were analyzed using the correlation between the heavy metals in PM₁₀. As a result of analyzing Asian dust entering the Gwangju region for 6 years, the average concentration of PM₁₀ measured in Asian dust was 148 ㎍/㎥, which was about 4.5 times higher than in non-Asian dust, 33 ㎍/㎥. A total of 13 Asian dust flowed into the Gwangju during 6 years, and high concentration of PM10 and heavy metals in that were analyzed in the C path flowing through the Gobi/Loess Plateau-Korean Peninsula. As a result of the correlation analysis, in case of Asian dust, there was a high correlation between soil components in heavy metals, so Asian dust seems to have a large external inflow. On the other hand, in case of non-Asian dust, the correlation between find dust PM₁₀ and artificial heavy metal components was high, indicating that the influence of industrial activities in Gwangju area was high.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.5
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• pp.495-501
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• 1994

This experiment was carried out to investigate the proper seeding methed for direct seeding culture of rice in puddled soil at ill-drained paddy field. Mangeumbyeo was seeded on May 11 with drill seeder attached to cultivater, dibbling seeder attached to transplanter and power dust blower. And to determine the proper flooding time after seeding, Mangeumbyeo was seeded on May 7 and June 1 with drill seeder. Emergence ratio wasn't significantly different between drill seeder seeding and dibbling seeder seeding but emergence was very low with power dust blower. Working hour for seeding was shortened in the order of power dust blower, drill seeder and dibbling seeder, and these seeding methods saved the working hour remarkably compared with machine transplanting of infant seedling by omitting the procedures of raising seedling and transplanting. Lodging occurred slightly in all seeding methods. However, yield wasn't significantly different between machine transplanting of infant seeding and direct seeding culture in puddled soil except power dust blower. When field was flooded on seeding date, the emergence period was shortened, emergence ratio was increased and weed occurrence was decreased. Yield was highest when flooding was done on seeding date as the number of panicle per m$^2$ and the number of spikelets per m$^2$ were higher than any other flooding time.

• Journal of Environmental Science International
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• v.9 no.6
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• pp.495-503
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• 2000

Dust samples were collected from 17 middle and high schools in the Jeonju-city. heavy metal concentrations were determined for the dry-deposited dusts from indoor and outdoor of classroom and playground of each sampling site. Concentrations of Cd, Cr, Cu, Ni, Pb and Zn in indoor\`s dusts were highly concentrated. Also heavy metal concentrations in outdoor\`s dusts were similar to that of indoor\`s dusts. Concentrations of Cd, Cu, and Zn in the dusts were much higher than the world average contents in soil and environmental orientation value. These levels are similar to those of the dust samples at middle schools located at Kangseo-gu and Yangchon-gu , Seoul. Playground dusts in 6 schools exhibited the enhanced heavy metal pollution with a pollution index (by Kloke) greater than 1.0. Most indoor and outdoor dusts exhibited the enhanced heavy metal pollution with a pollution index(by Cullbard et al.) greater than 1.0.

• Journal of Environmental Science International
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• v.25 no.5
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• pp.705-713
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• 2016

This study investigates the concentration sudden rise in fine particle according to resuspended dust from paved roads after sudden heavy rain in Busan on August 25, 2015. The localized torrential rainfall in Busan area occurred as tropical airmass flow from the south and polar airmass flow from north merged. Orographic effect of Mt. Geumjeong enforced rainfall and it amounted to maximum 80 mm/hr at Dongrae and Geumjeong region in Busan. This heavy rain induced flood and landslide in Busan and the nearby areas. The sudden heavy rain moved soil and gravel from mountainous region, which deposited on paved roads and near roadside. These matters on road suspended by an automobile transit, and increased fine particle concentration of air. In addition outdoor fine particle of high concentration flowed in indoor by shoes, cloths and air circulation.