• KSBB Journal
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• v.16 no.6
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• pp.632-637
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• 2001

The cells obtained from diesel contaminated site were tested for diesel degradation by culturing them on the culture medium that contained diesel as the only carbon source. Two strains that grew well in the culture media were separated: one formed white colony and another strain formed yellow colony. When they were cultured together, much higher diesel degradation was obtained compares to that of individual cell culture. Mixed culture of white and yellow colony forming strains grew well with 1%(v/v) diesel and the addition of growth nutrients increased the diesel degradation. Additional nitrogen source was efficient for higher diesel degradation (over 90%) when it was compared with that without nitrogen source. When mixed culture of white and yellow colony forming cells were applied to the soil column system contaminated by diesel, 30 mL/min of air flow rate was found to be sufficient to degrade diesel oil. The diesel degradation did not increase noticeably at higher flow rate. The addition of nitrogen source resulted in the increase in diesel degradability.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.1
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• pp.59-68
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• 2004

In this study, we investigated the concentrations of volatile organic compounds (VOC) in the ambient air of a small scale municipal waste landfill site. Seasonal sampling was carried out simultaneously at two sites, i.e. one in the center of the landfill area, and the other at a boundary site. Among 38 target VOC, toluene appeared to be the most dominant compound, followed by benzene. and xylenes. The higher levels of BTX imply that paint -containing materials and/or organic solvents are the most significant sources of the VOC in the landfill environment. Seasonal variations for the samples collected at the landfill site indicated that the VOC concentrations tend to be higher in the spring and fall season and lower in the winter season. In addition, night- time concentrations appeared to be generally higher than day-time. Such daily variation might be due to more stabilized atmosphere during the night-time. Similar patterns were also found in samples collected at a boundary site. This study demonstrated that the municipal landfill, although it is small -scaled, could be an important emission source of atmospheric VOC, particularly in the vicinities of the landfill. Thus, an appropriate control strategy is required to prevent any undesirable secondary pollutions from the environmental sanitary facilities such as landfill.

• Journal of Korean Society on Water Environment
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• v.26 no.6
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• pp.986-993
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• 2010

Spatially distributed on-site devices such as bioretentions and bioboxfilters are becoming more common as a means of controlling urban stormwater quality. One approach to modeling the cumulative catchment-scale effects of such devices is to resolve the catchment down to the scale of a land parcel or finer, and then to model each device separately. The focus of this study is to propose a semi-distributed model for simulating urban stormwater quantity and identifying best sites for spatially distributed on-site stormwater control devices in an urban drainage system. A detailed model for urban stormwater improvement conceptualization simulation is set up for a $0.9342km^2$.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.109.2-109.2
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• 2011

A photovoltaic system is getting the spotlight for a environment-friendly energy source. But its location is limited because a lot of land is necessary for photovoltaic arrays. Nevertheless, its dissemination is rapidly increasing more than 40 % every year and exceeded about 400 MW in 2009. The radical growth of a photovoltaic system aggravated a lack of sites, so that forests and farmland were destroyed. It is demanded to make use of a vacant lot or little piece of land for the way to solve the lack of sites and improve the location requirements for a photovoltaic system. General photovoltaic arrays are consist of a single layer structure and needs enough separation distances to maximize the amount of solar radiation and to eliminate influences by the shadow of other arrays. So that a large amount of land is required for the site. The solar cell arrays with long separation distances can not be placed in a small vacant lot and its site application efficiency is low. This study optimized photovoltaic arrays as multilayered structure with movable sleeves for the efficient photovoltaic in a small site. The existing photovoltaic arrays with a single layer structure were fixed or tracking systems. In this experimental equipment, photovoltaic arrays attached to the multilayers have rectilinear movement and rotary motion using sleeves. Therefore, shadow influences were removed and the generation capacity was improved. On the simulation result, generation increased by about 30% in the same site considering shadow influences and so on.

• 한국공간정보시스템학회:학술대회논문집
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• 2007.06a
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• pp.430-435
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• 2007

지금까지 우리나라의 GIS는 국가 중심의 GIS로, 사용자들이 적극 참여하거나 민간 산업 부분으로 확대되기에는 기술력, 비용 등의 한계를 갖고 있었다. 그래서 우리는 Open Source를 이용하여 종래 GIS의 한계를 극복하고 Google Map, Google Earth, Sketch Up을 연동한 Web Portal Site 구축을 통하여, 사용자들이 의사결정을 하는데 도움이 되는 효율적인 정보를 제공하며 이들이 곧 정보 창출의 주체가 되는 쌍방향적인 참여를 이끌어내고자 한다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.11a
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• pp.81-85
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• 1998

In the present study, the design method of containment walls is proposed by utilizing an existing site. The selected remedy for the Source Area of Operable Unit 2 at Hill Air Force Base stipulated containment of the pure-phase trichloroethylene contamination. The in-place-mixed wall construction was selected because of the irregular topography, small area of the site, and the requirement to reach depths of greater than 90 feet below ground surface. Bench-scale compatibility studies were performed for the containment wall mix design on three commercial bentonite clays. The samples were subject to screening tests and long-term tests for evaluation of changed soil properties when exposed to the contaminated groundwater.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.20 no.2
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• pp.191-198
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• 2010

The noise by the construction activities is one of the main issues in Korea. To prevent the noise from construction site, construction company installs temporary noise barriers along the construction site boundary. Normally sound insulation performance ($R_w$) of the temporary noise barriers made by metal or plastic is between 18 and 31 dB and metallic noise barriers are around 5 dB higher than plastic noise barriers. Sound absorption performance (NRC) of the temporary noise barriers are between 0.20 and 0.59 so it's difficult to characterize their acoustic performance. In this study, it has founded that sound insulation performance of the temporary noise barrier has been improved about 3dB by stick the high density acoustic sheet and insertion loss of noise barrier is getting increased as the source and receiver approached the temporary noise barriers.

• Korean Journal of Microbiology
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• v.13 no.1
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• pp.1-23
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• 1975

This experiment was designed to elucidate the environmental factors in rhizosphers of bamboo forest that affect the distribution and the population size of Azotobacter, and also to estimate the annual productivities of nitrogen fixed by Azotobacter species. The results of this experiment can be summarized as follows ; The rhizosphere of bamboo forest contained high free sugars as of 3-8 times more than non-rhizosphere (Bacon, 1968), and the contents of organic matter and amino acids of that are reltively higher than this. Because of high content of potassium, average of soil pH is near at 7.0. As above-mentioned enviromental factors, the population sizes of Actinomycetes, general fungi, general bacteria and Azotobacters are larger than those of non-rhizosphere and the ofllowings are general fungi and general bacteria by turns. Azotobacter is dependent upon the antagonistic Actinomycetes. The main carbon source for Azotobacter in nitrogn flxation at the rhizosphere was glucose and minors were fructose, maltose and sucrose by turns. Annual gains of nitrogen by Azotobacters in soil of bamboo forest within 10cm from surface are estimated as of 88.94 kg/ha at site A, 60.4kg/ha at site B and 67.38kg/ha at site C, respectively.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1915-1917
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• 2000

Laboratory experiments and on site measurements were conducted to detect partial discharges in GIS(Gas Insulated Switchgear) using the UHF(Ultra High Frequency) technique that has been applied many places in the world. Experimental results were in good agreement with calculation in locating a partial discharge source using mock-up GIS. Defect type and its location were inferred after a measurement on 345 kV GIS that showed some abnormal phenomenon. Precise examination inside the GIS coincided with the results inferred from the measurement. High reliability of UHF technique for site application was confirmed.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2006.04a
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• pp.237-238
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• 2006