• 지질공학
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• 제19권4호
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• pp.433-439
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• 2009

압축패커장치는 지하수관정의 지표하부오염방지시설의 개선을 위하여 개발한 장치이다. 이 장치는 안전잠금장치의 해제와 케이싱의 압축조작이 단순하여 시공이 간편하고, $4.5\;kg/cm^2$의 내압성을 갖고 있어 지하수 누출이 없도록 수밀성을 갖추고 있으며, 단일케이싱을 설치하며 그라우팅을 위한 확공은 300 mm로 굴착 가능하므로 시공비를 절약할 수 있다. 압축패커의 재질은 실리콘 고무를 사용하여 신장율이 590%이고 Pb, Cd, 페놀 등의 유해성분이 기준치 이하거나 불검출되어 우수한 환경성을 가지고 있다. 또한 시공비가 기존의 그라우팅 공법의 35~62% 이하, 환경신기술 제 47호인 팽창 패커 공법의 87% 이하로 시공이 가능한 경제적인 방법이며, 지하수 수질보전등에 관한 규칙, 제주도 지하수개발 이용시설 설치 및 관리기준, 환경부와 농림수산식품부의 소규모수도시설 운영관리 방안 지침 등 관련 법령규정에 적합한 제품이다.

• 아시안잔디학회지
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• 제16권1호
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• pp.19-30
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• 2002

경직된 지반의 물리성 개선재로서 rubber chip의 토양 내 혼합 또는 배토는 잔디의 생육과 지반의 이·화학성 및 중금속 추출 실험을 통하여 다음과 같은 결론을 얻었다. Rubber chip의 토양 내 혼합은 지면의 온도 상승효과를 가져왔으며 이는 겨울철의 동해방지 및 맹아출현기를 앞당길 수 있을 것이라 추정된다. 그러나 복사열이 높은 여름에는 rubber chip에 의한 표면, 지중 온도의 상승으로 잔디의 피해가 우려된다. 또한 토양 내에 rubber chip의 혼합함량(rubber chip 20%, 40%)이 많을수록 잔디의 발아와 생육 및 피복에 부정적인 영향을 끼쳤다. Rubberchip의 토양혼합은 지반의 이·화학성 변화에 크게 작용하지 않았으며 중금속 추출실험에서도 차이를 나타내지 않아 토양환경 오염이 없을 것으로 판단된다. Rubber chip을 배토용 재료로서 사용했을 경우, 경직된 토양구조를 개선시켜 주었다. 특히 통기작업 후 rubber chip의 배토는 지반의 표면탄성을 현저히 완화시켰다. 따라서 현재 우리나라에서 보수중이 거나 건설중인 연습구장, 보조구장에 재활용이 가능한 폐타이어 rubber chip을 지반 답압 개선용, 배토용 재료로서 사용이 가능할 것으로 판단된다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2003년도 추계학술발표대회 요약집
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• pp.443-443
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• 2003

• Preventive Nutrition and Food Science
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• 제8권2호
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• pp.196-199
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• 2003

We investigated the antagonistic effects of two lactococcal bacteriocins, nisin or lacticin NK24, on the growth and the survival of Listeria monocytogenes in vacuum or modified atmosphere-packaged ground beef, Ground beef was inoculated with approximately 3 log colony-forming units (CFU) of L. monocytogenes ATCC 15313 culture per gram of ground beef. Inoculated samples were blended with/without 100 AU/g nisin or lacticin NK24, and subsequently vacuum or modified atmosphere packed at 4$^{\circ}C$. Listeria in the bacteriocin-treated and control samples was subsequently isolated from both vacuum and modified atmosphere packs and enumerated as CFU on Listeria Isolation Agar medium. Microbial counts in ground beef treated with bacteriocin declined steadily, while those of non-treated beef samples increased steadily. The results obtained demonstrate that nisin inhibits the growth of L. monocytogenes more effectively than lacticin NK24 at 100 AU/g. The use of lactococcal bacteriocins, such as nisin or lacticin NK24, in vacuum or modified atmosphere packaging offers a promising approach for eliminating or reducing the risk of L monocytogenes contamination in ground beef.

• 한국환경농학회지
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• 제17권1호
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• pp.59-64
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• 1998

The environmental problem of the rural area has been accelerated in soil as well as water. Soil contamination is usually caused by improper operation of landfills, abandoned mine fields, accidental spills, and illegal dumpings. Once soil contamination is initiated, pollutants migrate and may cause groundwater contamination which takes much effort for remediation. Early detection, therefore, is important to prevent further contamination. Electrical resistivity method was used to detect soil contamination, but it was not effective to the heterogeneous condition. Static cone penetrometer test (CPT) has been used widely to investigate geotechnical properties of the underground. In this study, electrical resistivity method and CPT are combined to improve the applicability of it. The pilot test was performed to examine the variation of electrical resistivity with different soil minerals and pore fluid characteristics. Soil samples used were poorly graded sand, silty sandy soil, and weathered granite soil. For all the cases, electrical resistivity decreased with increasing of moisture content. Soil mineral also affected the electrical resistivity significantly. Above all, leachate addition in the pore fluid was very sensitive and caused decreasing of electrical resistivity markedly. It implies that electrical resistivity method can be applied to investigate pollutant plume effectively. This is specially sure when the sensors contact the contaminated soils directly. The CPT method involves cone penetration to the ground, therefore, underground contamination around the cone could be investigated effectively even for heterogeneous condition as it penetrates if electrical resistivity sensors are attached on the cone.

• 한국농공학회논문집
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• 제50권6호
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• pp.15-24
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• 2008

In general, ground pollution can be classified with soil pollution and underground water pollution. And ground pollution contaminates the land with garbage dumps and other harmful waste products as heavy metals that can also eventually enter our water supply. This study was conducted to define a characteristics of the electrical resistivity and the permittivity of weathered soil that was contaminated with heavy metals as Mercury and Arsenic. It is not easy whether contamination of soil as subsurface contamination is decided or not and at an early stage especially do that. Therefore the electrical resistivity and the permittivity were used to make up for this defects. These methods are more economical and more effective than the existing methods. And variation of the electrical resistivity and the permittivity values were found against the change of concentration of Mercury and Arsenic aqueous solutions and measuring frequency. These analyzed results indicate that the electrical resistivity and the permittivity tend to decrease against increasing measuring frequency. The electrical resistivity and the permittivity are also found to show the function of frequency.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.23-26
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• 2004

Methyl Tertiary-Butyl Ether is one of several fuel oxygenates added to gasoline to improve fuel combustion and reduce tile resulting concentration of hydrocarbon. Thus, MTBE transfer readily to groundwater from gasoline leaking from Underground Storage Tank. Therefor, there are significant risks and costs associated with the water contamination. MTBE is far more water soluble than gasoline hydrocarbon. The purpose of the this study is to test the ability of ground tire with facultative bacteria. Bacillus brevis, to sorb MTBE. The process is consisted both batch and column experiment to determine the sorption capacity. And Biofilm is observed by SEM in the column. Finally, it is clear that ground tire represent an attractive and relatively inexpensive sorption medium for a MTBE. The authors can surmise that to determine the economic cost of ground tire utilization, tile cost to sorb a given mass of contaminant by ground tire will have to be compared to currently accepted sorption media. and Bacillus brevis strain was eliminated on MTBE, too. The biobarrier that ground tire with bacteria, has potential for use in the remediation of MTBE-contaminated environments.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.450-452
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• 2004

Using factor analysis and bivariate comparisons of major components in ground water, three geochemical processes were identified as controlling factors of ground water chemistry; 1) natural mineralization by water rock interactions, 2) effect of seawater which includes salinization by seawater near seashores and deposition of sea salt, and 3) nitrate contamination by N fertilization. Contribution of rainfall was also estimated from the measured composition of wet deposition. The geochemical processes were separated using total alkalinity as an indicator for natural mineralization, Cl for effect of seawater, and nitrate for N fertilization. Relatively high correlation of major components with nitrate suggests that nitrification of nitrogenous fertilizers significantly affects ground water chemistry. Total cations derived from nitrate sources have good linearity for nitrate in equivalent basis with a slope of 1.8, which is a mean of proton production coefficients in nitrification of two major compounds in nitrogenous fertilizers, ammonium and urea. Contribution of nitrate sources to base cations, Cl, and SO$_4$ in ground water was determined considering maximum contribution of natural mineralization to estimate a threshold of the effect of N fertilization for ground water chemistry, which shows W fertilization has a greatest effect than any other processes in ground water with nitrate concentration greater than 50 mg/L for Ca, Mg, Na and with concentration greater than 30 mg/L for Cl and SO$_4$.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 가을 학술발표회 논문집
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• pp.247-254
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• 1999

In recent years there has been a steady increase in geoenvironmental engineering projects where geotechnical engineering has been combined with environmental concerns. Many of these projects involve some investigation of contaminant in the ground. There are many techniques such as geophysical, drilling, sampling, and pushing techniques for investigation of contaminated ground. The most rapidly developing site characterization techniques for geoenvironmental purposes Involve direct push technology, that is, penetration tests. In this study, the envi-cone penetrometer system is developed by modification of traditional cone penetration test. The electrical resistivity sensor, pH sensor, thermometer are installed in envi-cone penetrometer system. This envi-cone penetrometer system provides a continuous profile of measurements, and it is rapid, repeatable, reliable and cost effective.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2009년도 정보통신설비 학술대회
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• pp.258-261
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• 2009

This paper proposes an earthing system without ground connection. As a Green IT Environmental Solution, Internal-external surge and other unnecessary electric currents are converted into energy and through a discharge the signal is reduced. It's a structure that discharges through a neutral electric transformer. The results show that the electric potential rising of the earthing system proposed in this paper are approximately below the half and the discharge currents increased approximately 9 times when compared to existent earthing systems. This earthing system is economical, easy to install and can solve environmental contamination.