• Geotechnical Engineering
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• v.13 no.6
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• pp.37-44
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• 1997

In this paper, the effects of crude oil contamination on the geotechnical properties of sand such as compaction characteristics, shear strength, permeability, and bearing capacity are presented. The test results indicate that the compaction characteristics are somewhat influenced by oil contamination. The angle of internal friction of sand based on total stress analysis decreases due to the presence of oil within the pore spaces in Band. The bearing capacity of sand is significantly influenced by oil contamination.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1362-1364
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• 1995

In this paper, the automatic device for measuring the salt contamination on insulators was developed. The device consists of electronic insulators, measuring system, monitoring system, and printer. It was shown that the level of salt contamination measured by the developed device is similar to that measured by the brush cleaning method. Therefore, the developed automatic measuring device can be used in field, in order to predict the cleaning time of insulators and prevent the failure due to the salt contamination.

• Journal of Environmental Impact Assessment
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• v.4 no.1
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• pp.17-23
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• 1995

To assess preliminarily the contamination potential of water resources including groundwater owing to the hydrogeological characteristics of landfill site and the potential impact to humans and animals through contamination of water resources by leachate, "Landfill Site Preliminary Assessment Model(LASPAS)" was contrived. LASPAS could help them proritization of remediation of landfil sites by the convenient and relatively simple evaluation method of landfill site features. LASPAS was designd to aliot numerical ratings to landfill site related factors undermentioned; 1) hydrogeological factors such as hydraulic conductivity of aquifer, thickness of confining layer over aquifer, topographical slope, net recharge, and subsurface containment 2) water resources contamination factors of impacts on receptors such as proximity to drinking water supply, substitutability of drinking water supply, type of use of water resources, known impact on drinking water supply, and flood potential.

• Journal of the Semiconductor & Display Technology
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• v.14 no.1
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• pp.45-49
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• 2015

Process gases with vapor or liquid phase as well as gas phase may experience alteration in itself or be contaminated in the fluid pipe to the process chamber. And thus it result in as particles or defects on the substrates in semiconductor, LCD, LED manufacturing. Purifiers and filters are used for control of contamination. However, none of detection device is available in the delivery line. In this paper, we propose simple device with lighting and sensing in order to predict contamination of the fluid or the tube wall. For some general purpose gases, it showed constant voltage output regardless of the flow rates. But, the smoke and the moisture in the air lowered the figure due to its concentration. Numerical values for several solid and liquid media were obtained. And, the operating temperature tendency was investigated.

• Journal of Hydrogen and New Energy
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• v.28 no.4
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• pp.331-337
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• 2017

Proton Exchange Membrane Water Electrolysis (PEMWE) is one of the most popular and widely used methods for hydrogen production. PEMWE contributes to eco-friendly system via its energy storage system application, hence making it environmentally friendly to use. However, its main drawback is contamination of proton exchange membrane during water electrolysis. Existing cation such as magnesium, calcium and the likes are the cause for membrane contamination. As a result, the cation contamination give rise to degradation of performance of electrolysis and the reverse electrolysis is effective method to remove cation.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.4
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• pp.541-546
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• 2012

This study investigates the detection system of oil pollution level using single optical fiber sensor. This study focus on sensing of oil pollution by moisture and iron powder which are representatives of oil pollution factor. In addition, It is placed that the water and iron powder as an oil pollution factor in the oil tank which is the oil circulation in. The oil pollution detection system was measured by the changing of intensity of light and sensing gap. The result of this experimentation not only confirmed the contamination by moisture volume in the oil tank from the section 190ppm to 540ppm, but also monitored the contamination by iron volume from the section 1200ppm to 3500ppm. This study confirmed effectiveness of this detection system using optical fiber sensor. There is expectations of measuring another section by various optical fiber sensor.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.209-212
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• 2004

Soil environment has not received much attention from the environmental impact assessor community although soil contamination may affect human health and the eco-system. This study was the first trial to discuss the role and importance of soil environment in the environmental impact assessment(EIA) and suggest possible environmental impact assessment schemes for soil. The objectives of the study were to show the effects of soil contamination on human health, the environment and the social community, suggest efficient EIA schemes in Korea and establish the basic concepts of soil environment assessment involving fate and transport of contaminants and its risk.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2006.11a
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• pp.86-87
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• 2006

The hatchery sanitation has a significant impact on chick quality. This study was carried out to investigate the bacterial contamination in the broiler hatchery. The aerosol bacterial contamination was low except for the operating hatcher that the bacterial counts were measured almost over 300 counts/64cm$^{2}$. The bacterial contamination of the facilities and equipments had a similar tendency as compared with the aerosol bacterial contamination. More than six groups of the Salmonella species were isolated almost from the hatcher and the related facilities and equipments. Also, in this study, we compared the effects of four methods of 37% formalin adminstration in hatcher. At hatch, the aerosol bacterial counts in hatcher receiving 37% formalin as constant rate infusion method during hatching were significantly lower than in each hatcher receiving 37% formalin once at transfer and not receiving 37% formalin, respectively(p<0.05).

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2001.11a
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• pp.199-202
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• 2001

This paper presents the correlation on the contamination degree and weather conditions using the multiple regression of the statistic method. The cotamination is a significant factor in the insulation system. The major factor is natural contamination, and the most is the salt. The salt contamination is occured by the weather conditions. The weather contaminations are wind, precipitation, temperature, relative humidity, etc. The effects of those are different, and the correlation is showed numerically by using the multiple regression method of the statistic method. With this, the estimation of the equivalent salt deposit density(ESDD) becomes possible by the changes of the weather conditions.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.11a
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• pp.189-194
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• 1998

Geochemical study was carried out to find out the distribution of metals and cyanide in soil in the vicinity of the abandoned Keum-Jung mine. Chemical analysis showed that content of As in soil around tailings exceeded 15mg/kg, Korean standard of soil contamination in the farm land. That means the contamination of soil by As is due to input of tailings. According to total decomposition of tailings, As was highly concentrated in tailings. However the water in tailings impoundment was changed to acidic and contaminated by metal and sulfate because the tailings in the top of the tailings impoundment had been oxidized. Acid mine drainage contaminated the water course in the vicinity of the paddy soils. The proper measures are required to prevent contamination of the soil and water in the vicinity of the Keum-Jung mine.