• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.5
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• pp.659-672
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• 1994

Four simple plotting techniques using the distribution of individuals among species were applied and the results discussed to evaluate the methods for detecting organic pollution-induced perturbation in marine benthic communities in Chinhae Bay, Korea: Rarefaction method, Abundance-Biomass Comparison method, Log-Normal Distribution method and Rank-Frequency Diagram method. Their distribution curves offered more information on the community structure than other frequently used diversity indices and distinguished clear evidence of an effect of environmental pollution with gradient. However, the Abundance-Biomass Comparison method could not be considered applicable due to the presence of larger slowly growing K-strategists in a polluted area of the inner Chinhae Bay, Korea.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.10a
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• pp.147-149
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• 2004

본 연구는 국내산 돈육의 오염도 및 병원균의 분포를 조사하기 위해 실시되었다. 가공전의 원료육과 절단 가공 후의 포장육의 병원균 오염도 비교시, 원료육 38.7% 포장육 32.3%로 원료육의 오염도가 더 높았다. 이는 비위생적인 도축시의 오염으로 추정이 가능하며 현재 의무적으로 실시하는 도축장의 HACCP 관리기준을 더욱 준수하여 위생안전성을 높여야 한다고 판단된다. 병원균에서는 L. monocytogenes의 분리율이 가장 높았으며 초기 오염이 제어되지 않을시, 저온성장균이라는 특징을 가진 증식은 L. monocytogenes 보관온도 준수만으로는 억제할 수 없다고 사료된다. 또한 축산물 취급 장소별로도 상이한 결과를 보였으며, 가장 낮은 오염 수치인 8.3%와 가장 높은 81.8%의 차이로 보아, 원료 축산물과 관련하여 취급 장소의 위생상태가 축산물의 안전성에 많은 영향을 끼친다고 사료된다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.04a
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• pp.101-102
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• 2002

동북아시아 지역은 전 세계적으로 인구가 조밀하고 경제발전 속도가 빠른 지역으로, 이에 따라 막대한 양의 대기오염물질이 배출되고 있다. 이 지역의 대기오염 특성으로는 (1) 막대한 양의 인위적인 대기오염물질 배출, (2) 흙먼지의 배출, (3) 편서풍을 들 수 있다 (문길주 등, 1996). 본 연구에서는 동북아시아 지역을 대상으로 기류이동의 변화에 따라 대기오염물질의 분포가 어떻게 달라지는가를 보고자 하였으며, 이를 위하여 우리나라 시간으로 1999년 5월 6-7일과 5월 11-12일의 바람장 및 대기오염물질의 농도 변화를 비교 분석하였다. (중략)

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.27-30
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• 2004

오염토양의 pH는 7.47에서 7.97까지의 범위로 약 알카리성이며, 토성은 80% 이상이 0.425 -2 mm 범위에 분포하는 coarse sand의 성질을 가지고 있다. 토양 입도 분석 및 농도 분포의 결과로 볼 때, 입도 2mm 이하의 토양 중 0.85-2.00 mm 범위에 있는 토양이 약 60% 이상의 오염물질을 포함하고 있다. 세척제로 고려된 용액 중 As 용출효율의 결과를 살펴보면, H$_3$PO$_4$ 및 citric acid가 100% 제거율을 보이고 있어 가장 효과적임을 나타내고 있다.

• Progress in Medical Physics
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• v.13 no.1
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• pp.1-8
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• 2002

Accurate knowledge of the distribution of contamination electrons ( which comes from mainly gantry head by Compton scattering, pair production, and tray: henceforth called leptons ) at the surface and in the first centimeters of tissue is essential for the clinical practice of radiation oncology. Such lepton tends to reduce or eliminate the ‘skin-sparing’ advantage of megavoltage photon beam radiotherapy, This information is needed to prescribe a absorbed dose to a skin volume at a few millimeter depth in high energy therapeutic radiation photon beam All experiments were done with 15 MV photon beam from a dual energy linear accelerator (Clinac 1800, Varian). Field size is defined by ranged from 10.0$\times$10.0 to 30.0$\times$30.0 $\textrm{cm}^2$. The absorbed dose and distribution of leptons in therapeutic radiation beam (15 MV) are investigated by means of variable blocked beams of 30.0$\times$30.0 $\textrm{cm}^2$ and dose beam profiles partly removed leptons with a copper plate. A numerous leptons mainly are distributed as shape of broad cone in the central photon beam and leptons path length in the water are shorter than 2.5 cm because of the leptons energy having around 3.0 MeV. These results clearly appears that the subtraction of leptons from the total depth dose curve not only lower the absolute dose in the buildup region and surface dose, it also causes a shift of d$_{max}$ to a deeper depth.

• Journal of Korean Society for Geospatial Information Science
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• v.13 no.1 s.31
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• pp.81-87
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• 2005

This paper is aimed at allocation analysis of TMS networks using GIS. Allocation analysis by TMS air pollution data in Incheon Metropolitan City shows that the land usage patterns of the TMS surrounding area have been changed. And land usage patterns shows that the most TMS was established in residential area. Therefore, it needs to relocation and additional establishment of TMS. If the existing TMSs would move into appropriate positions and proportional distribution method by means of population would be used, additional establishment of TMS could be minimized.

• Korean Journal of Environmental Biology
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• v.23 no.2 s.58
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• pp.120-128
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• 2005

This study was compared the flora and distribution of hydrophytes with physicochemical environment in the 14 sites selected in Yeongsan River through Gwangju Metropolitan city from March to October, 2003. In this survey, hydrophytes were classified 94 taxa; 35 families, 68 genera, 85 species and 9 varieties. It was compared the physicochemical characters with the hydrophytes distribution in each stream according to the index of contamination. Persicaria japonica and Rumex crispus were dominated at Youduk-Dong, the most contaminated area. Aquatic contamination sensitive floating-leaved plants and submerged plants were not identified. Hwangroung River and Yeongsan River area were a little contaminated area, appeared to good vegetation such as Phragmites japonica, Persicaria thunbergii and Miscanthus sacchariflorus. The stream of Youduk-Dong, the lower reaches of Gwangju-cheon was not grown with hydrophytes because of contamination by inflow of life sewage; therefore it is required to persevere in the townsmen's efforts for improvement of water environment.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.88-88
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• 2020

수심평균 2차원 혼합모형은 하천환경에서 다양한 용존성 오염물질의 혼합현상을 모의하기 위해 널리 활용되어왔다. 2차원 혼합모형에서 분산계수는 하천의 전단 흐름에 의해 야기되는 오염물질의 퍼짐 현상을 표현하는 중요한 인자로서 작용하기 때문에 정교한 오염물질 혼합거동을 모의하기 위해서는 적합한 분산계수를 산정하는 것이 필수적이다. 분산계수를 실험적으로 산정하는 방법으로는 크게 모멘트법과 추적법으로 나뉘며, 비정상상태의 혼합거동에 대해 종방향 및 횡방향 분산계수를 동시에 산정할 수 있는 방법은 추적법 계열의 2차원 유관추적법(2D STRP)이 유일하다. 본 연구에서는 하천에 유입된 오염물질의 2차원 혼합해석을 위한 수치모형을 개발하였으며, 개발된 모형의 수치해를 바탕으로 다양한 Peclet 수의 범위에 대해 기존연구에서 제시된 2D STRP의 적용범위 및 성능을 정량적으로 분석하였다. 분석된 정보를 바탕으로 기존 2D STRP의 한계를 극복하기 위한 개선된 2차원 유관추적법(2D STRP-i)을 개발하고, 사행하천을 모형화한 실규모 하천실험시설에서 검증하였다. 기존 2D STRP의 성능평가 결과, Peclet 수가 낮은 조건일수록 농도분포의 예측 정확도가 감소하는 경향을 보였으며, 하안 경계에 도달하는 농도가 증가할수록 부정확한 결과를 초래하는 것으로 나타났다. 본 연구에서는 기존 2D STRP의 한계를 보완하여 더욱 정확한 분산계수를 산정하고자 하안 경계면 조건을 고려한 2차원 유관추적법(2D STRP-i)을 개발하였다. 2D STRP-i는 직교-곡선좌표계 기반의 2차원 이송-분산 방정식을 바탕으로 횡방향 유속분포 및 하안 경계조건을 고려할 수 있도록 개선되었다. 2D STRP-i는 공간적으로 상이한 이송효과 및 하안경계 조건을 적절히 반영함으로써 농도분포의 예측 정확도를 개선 시키는 것으로 평가되었으며, 하안경계면에서 농도가 증가하는 구간에서 기존 2D STRP의 결과와 비교하여 더욱 정확한 농도분포 및 분산계수를 제공하는 것으로 밝혀졌다.

• Korean Journal of Environmental Biology
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• v.24 no.1 s.61
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• pp.38-45
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• 2006

Ecological characteristics of microbial populations inhabiting heavy metal polluted soil were investigated. The samples were collected from 293 sites around an factory and industry at Gyeoungsangbuk-do. We measured the contents of seven heavy metal elements (Cd, Cu, As, Hg, Pb, $Cr^{6+}$, CN), seven sites have been seriously contaminated by mercury and chrome. A quantitative evaluation of microbial populations in mercury and chrome contaminated soil was examined by using plate count method. Bacterial numbers in polluted soil samples ranged from $7.4X10^5\;to\;9.3X10^7\;cfu\;g^{-1}$, about $10\sim100$ fold less than the count for the unpolluted soil. Moulds were not detected in chrome polluted soil. The log values of actinomycetes of each contaminated soil samples were log ranged from 6.18 to 7.52. The ratio of actinomycetes was similar to unpolluted soil. The investigation showed actinomycetes to be the major microbial population inhabiting the mercury and chrome polluted soil. Thirty-one isolates among the total isolates were examined for antibacterial activity. These isolates were identified based on a phylogenetic analysis using 16S rRNA gene nucleotide sequences, they were categorized in three major phylogenetic groups, belong to the Streptomyces (6 strains), Saccharopolyspora (3 strains), Nocardiodes (1 strain). On the phylogenetic tree, the clade consisting of five isolates were distantly related to all of the established Streptomycetes genera, indicating the possibility as members of new species.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.7
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• pp.1295-1305
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• 2000

Status of the contaminated sediments in Lake Paldang was investigated. Sediment samples were taken at 34 points and analyzed in terms of ignition loss, CODer, total P and total N. The contamination level did not show any significant variation with depth of the sediments, which indicated the contaminants were recalcitrant. The type of P in the sediment was analyzed, and the sum of adsorbed P and NAI-P, that can be re-solubilized under the reductive condition, was found to be 20-30% of the total P. From the analysis of the water quality change along with the flowing path, it would be concluded that the effect of the sediments on the water quality is insignificant yet in Lake Paldang. However, long term analysis covering at least four seasons should be continued in order to get a more reliable conclusion. A depth profile map of the sediment in Lake Paldang was provided.