• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.354-355
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• 2003

In this study, a risk-based cleanup approach using the leaching potential was suggested for the soil vapor extraction (SVE) process. A multi-component model was adopted with local equilibrium assumption (LEA), and Raoult's law was applied to estimate the leaching potential for BTEX. Finally, a risk analysis was conducted based on the leaching pontential calculated. To complete the feasibility of this approach, more investigations and discussions will be required in future.

• 한국안전학회지
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• 제24권6호
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• pp.72-78
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• 2009

차량수리작업장에 일반적으로 사용하고 있는 HDI의 노출은 직업성 천식을 발생시키는 주요 원인이 된다. 비록 피부나 눈의 오염이 흡수경로로 고려되고 있음에도 불구하고 이들의 폭로에 관한 작업장의 노출허용 기준이 규정되어 있지 않으므로 많은 실험 자료들이 제공되어져야 한다. 따라서 이 연구는 피부, 눈 그리고 호흡보호구와 눈보호구의 표면에 대한 HDI의 오염정도를 확인하였으며, 손잡이, 작업대 그리고 분사건과 같이 다양한 오염표면이 있다는 것도 명확히 하였다. 상대적으로 짧은 시간의 분사임에도 불구하고 목, 이마, 손등, 팔과 손목 등에서 채취한 시료의 많은 부분(47~80%)이 HDI오염에 양성이었다. 분사실 내부에서의 오염정도는 좋지 못한 작업여건이나 보호경과 같은 부적절한 개인보호구 때문에 분사실 외부의 오염정도보다 일반적으로 높다. 경험이 있는 페인트 공보다 초보자들의 폭로수준이 높은 것은 안전이나 보건의식의 결여 때문인 것으로 사료되고, 보호구내부의 오염 정도는 호흡기관, 피부 및 눈의 잠재적인 노출을 야기할 것이다. 작업자 14명중에서 4명의 눈물시료로부터 HDI양성반응을 보였으며, 이것은 부적절한 눈 보호구에 의한 것으로 나타났다. 호흡기의 과민반응을 포함한 건강징후에 관여되는 피부와 눈의 노출 잠재성을 고려해볼 때 실질적 자료는 작업자들의 근무여건개선, 적절한 보호구의 선택과 사용 그리고 관리의 중요성을 잘 보여 주고 있다.

• 한국물환경학회지
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• 제37권4호
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• pp.296-305
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• 2021

This work investigated heavy metal pollution in surface sediments of rivers in Busan, Korea. Surface sediments were analyzed in order to conduct contamination assessment of organic matter, nutrients, and heavy metal concentrations. Contamination assessment of heavy metals was conducted using geoaccumulation index (I_geo), pollution load index (PLI), and potential ecological risk index (RI). Accumulation of organic matter and nutrients were affected by water discharged from sewage treatment plant. The concentrations of organic matter and nutrients were found to be greater in points which were close to the sewage treatment plant more than points furthest. The concentrations of Pb, Zn, Cu, Cd, Hg, As, Cr, and Ni were found to be greater in surface sediment more than in the background. The mean concentrations of heavy metals were in the order of Zn (323.5 mg/kg) > Cu (70.5 mg/kg) > Pb (39.8 mg/kg) > Cr (33.4 mg/kg) > Ni (13.5 mg/kg) > As (9.4 mg/kg) > Cd (0.84 mg/kg) > Hg (0.092 mg/kg). The result of geoaccumulation indices indicated that Hg > Cr > Cu > Ni > Zn > As > Pb > Cd were found in order of severe contamination by heavy metals. From PLI and RI analysis, it was evident that the Suyeonggang 2 was the most contaminated river.

• 한국건설순환자원학회논문집
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• 제9권2호
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• pp.161-166
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• 2021

본 연구는 순환골재에서 발생하는 오염물질의 특성과 오염가능성을 평가하기 위해 생산제품 순환골재의 용출시험을 실시하였다. 순환골재에 포함된 pH, 전기전도도, 탁도, TN, TP, COD 그리고 중금속 농도는 입경이 작을수록 높은 농도를 나타냈다. pH 농도는 9.9~11.4 범위로 토양보다는 높았으나 중금속 농도는 토양오염우려기준의 1지역 기준치 이내로 조사되었다. 용출시험 결과, 오염가능성은 입자크기가 작을수록 높아지는 것으로 나타났다. 특히, 전기전도도와 탁도는 잠재적인 수질오염원이며, 10mm 이하의 순환골재는 용존성과 입자성 오염물질을 발생시킬 수 있기 때문에 잠재적인 오염원으로 평가되었지만, 현재 적절한 관리기준은 없다. 순환골재로 부터 수질오염 가능성을 평가한 결과, 오염가능성이 가장 높은 항목으로는 pH, 오염가능성이 낮은 항목으로는 TN, TP, 오염가능성이 가장 낮은 항목으로는 중금속으로 나타났다.

• 환경영향평가
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• 제19권2호
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• pp.107-116
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• 2010

In this research potential liquation of contaminants from surrounding soil to a reservoir in an island was studied to investigate the cause and route of contamination of Baengyeong-myeon reservoir. Soil of Baengyeong-myeon reservoir consists of $SiO_2$ and has a high iron content because of geological characteristics of its country rock. From the field investigation and simulation study it was found that highly accumulated carbon content in the reservoir sediment was incurred from ground water, which provides a good habitat for microbes. And the liquation, the cause of organics growth, occurs mainly on the bottom of the reservoir consisting marine clay layer once used as farmland. So dredging of the sediment of reservoir and replacing with valley soil is suggested to prevent continuous contamination of a reservoir in an island due to COD production.

• 영어영문학
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• 제57권6호
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• pp.1089-1109
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• 2011

In an attempt to demonstrate in context of Nietzsche's "overman" (ubermensch) and Heidegger's "Being-in-the-World" (Dasein) the collective human efforts to overcome humanism in crisis, I will provide the ground for the poetics of overcoming, the ground which are based upon the double movements of transhumanism and transnationalism. For this purpose, I will turn to the theories of two distinctive poets who reveal and disreveal their truths about the subjecthood or the subjectivity in terms of overcoming: Christopher Dewdney for posthuman transhumanity and Dionisio D. Martinez for transnational cultural contamination Transhumanism represented by Christopher Dewdney manifests an interfusion of outside and inside, thereby collapsing the boundary between the mind and the world, and provides a breakthrough from the limitedly defined mind to the transhuman perspective of overcoming by using terminalogy and techniques from science and technology. The emerging transhumanism reflects the growing interdependence between humans and bio technologies, and suggests a potential improvement of human beings. The main argument of transhumanism is that we humans can and should continue to develop in all possible directions, by overcoming our human limitations by shedding the body and having the disembodied consciousness which will liberate our mind. Kwame Anthony Appiah's "cultural contamination" is another form of overcoming as well as a way to otherness, a counter-ideal of cultural purity which sustains authentic culture, reversing the traditional binary opposition between enriching authenticity and threatening hybridization. Dionisio Martinez's poetry sublimates the negative side of Appiah's concept of contamination, by redeeming the value of the Appiah's list of the ideal of contamination such as hybridity, impurity, intermingling, the transformation that comes of new and unexpected combinations of human beings, a bit of this and a bit of that is how newness enters the world. When a poetic subject is doubly exiled and doubly homeless away from his/her native homeland and home of native language, one has no more identification with the authentic culture of both home and away, but rather anticipates a new identity as a transnational subject to cross the bridge beyond cultural authenticity and to enter into the field of cultural contamination.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.459-462
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• 2004

This study assesses groundwater vulnerability to contaminants in 12 administrative districts of the city of Changwon, using DRASTIC technique. DRASTIC was originally applied to situations in which the contamination sources are at the ground surface, and the contaminants flow into the groundwater with infiltration of rainfall. However, groundwater contamination in urban areas can also be related to excessive pumping resulting in a lowering of the water level. The correlation coefficient between minimum DRASTIC indices and the degree of poor water quality for 10 districts is low as 0.40. The correlation coefficients between minimum DRASTIC indices and the groundwater discharge rate, and between minimum DRASTIC indices and well density per unit area are 0.70 and 0.87, respectively. Thus, to evaluate the potential of groundwater contamination in urban areas, it is necessary to consider other factors such as groundwater withdrawal rate and well density per unit area with ratings and weights as well as the existing six DRASTIC factors.

• 한국환경복원기술학회지
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• 제11권4호
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• pp.1-11
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• 2008

This paper analyzed the status of contaminated soils in order to manage it efficiently in Incheon using Geographic Information System (GIS) and investigated the concepts and techniques of the GIS and interpolation method. GIS technique is applied to the analysis of soil quality monitoring data. The purposes of this research are to assess the soil contamination of Incheon metropolitan area and to analyze the existing contents of heavy metals (Cd, Cu, As, Hg, Pb, $Cr^{+6}$) and pH in soil. The samples had been collected from year 1998 to year 2002 by the Soil Contamination Monitoring Network. The soil quality monitoring results were imported with the geographical information of the monitoring programs in capital area. It is found that currently available GIS technique has a great extend of potential for soil quality management. From the analysis of soil quality monitoring results, the GIS application demonstrates the poor soil quality in the central capital area and the it is improved as it travels down to the suburb area. Concerning about the data interpolation, the discrepancy caused by applying different method was ignorable, although Kriging method is further developed.

• Current Photovoltaic Research
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• 제6권1호
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• pp.17-20
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• 2018

The dependency of the photovoltaic performance of p-/n-type silicon solar-cells on the metallic contaminant type (Fe, Cu, and Ni) and concentration was investigated. The minority-carrier recombination lifetime was degraded with increasing metallic contaminant concentration, however, the degradation sensitivity of recombination lifetime was lower at n-type than p-type silicon wafer, which means n-type silicon wafer have an immunity to the effect of metallic contamination. This is because heavy metal ions with positive charge have a much larger capture cross section of electron than hole, so that reaction with electrons occurs much more easily. The power conversion efficiency of n-type solar-cells was degraded by 9.73% when metallic impurities were introduced in the silicon bulk, which is lower degradation compared to p-type solar-cells (15.61% of efficiency degradation). Therefore, n-type silicon solar-cells have a potential to achieve high efficiency of the solar-cell in the future with a merit of immunity against metal contamination.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제18권5호
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• pp.1301-1316
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• 2024

In modern warfare, missiles play a pivotal role but typically spend the majority of their lifecycle in long-term storage or standby mode, making it difficult to detect failures. Preemptive detection of missiles that will fail is crucial to preventing severe consequences, including safety hazards and mission failures. This study proposes a contamination-based stacking ensemble model, employing the local outlier factor (LOF), to detect such missiles. The proposed model creates multiple base LOF models with different contamination values and combines their anomaly scores to achieve a robust anomaly detection. A comparative performance analysis was conducted between the proposed model and the traditional single LOF model, using production-related inspection data from missiles deployed in the military. The experimental results showed that, with the contamination parameter set to 0.1, the proposed model exhibited an increase of approximately 22 percentage points in accuracy and 71 percentage points in F1-score compared to the single LOF model. This approach enables the preemptive identification of potential failures, undetectable through traditional statistical quality control methods. Consequently, it contributes to lower missile failure rates in real battlefield scenarios, leading to significant time and cost savings in the military industry.