• Journal of Korean Society of Environmental Engineers
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• v.37 no.1
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• pp.45-51
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• 2015

PBDEs (polybrominated diphenyl ehters) are rarely dissolved in water due to their strong hydrophobicity and large molecular mass so not many researches were done in aqueous environment compared to other environmental compartments. However, the mass loading from wastewater treatment plant into aquatic environment, re-suspension from bottom sediment and partitioning from floating particles and colloids may not be negligible. It is, therefore, important but also difficult to investigate PBDEs in water environment. Recent overcoming resolution towards this barrier to monitor hydrophobic organic compounds in aquatic environment is using passive sampling technique like semipermeable membrane device. By using passive sampling, it might be possible to obtain long-term reproducible monitoring result and detect the trace amounts of PBDEs, with controlling fluctuation of surrounding environmental factors during the sampling event. So therefore, this study is purposed to confirm the possibility of using SPMD (semi-permeable membrane device) as water monitoring tool. Grab samples, composite samples and SPMDs were applied in river bank to evaluate the concentration difference and temporal fluctuation by various water sampling method, and to assess the water concentration prediction capability of SPMD for the PBDEs.

• Journal of Korea Society of Industrial Information Systems
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• v.16 no.4
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• pp.37-44
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• 2011

This paper was development of surface contamination automatic smear sampling for measuring radioactive contamination in radiation controlled area of nuclear facility. In indirect method a smear paper are used manually. Activity on the smear paper is affected by varying the pressures applied, by the smearing time, by the difference of ares sampled during smearing. By means of these there are erroneous. In the future the apparatus will be developed as a portable apparatus measuring smear activity automatically by adding radiation detection instrument.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.372-373
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• 2003

오늘날 강수의 오염도는 대기오염의 중요한 지표가 되고 있으며, 특히 산성화된 강수는 생태계에 심각한 악영향을 주고 있어 전세계적으로 이에 대한 연구가 지속적으로 이루어지고 있다. 우리나라에서도 환경부 및 지방자치단체에서 산성비 측정망을 운영하면서 강수의 산성도 및 수용성 이온성분의 농도 측정을 수행하고 있으나 현재 강수자동채취장치와 수동채취장치를 같이 사용하고 있어 그 분석자료의 정도관리에 상당한 문제점이 있는 것으로 드러나고 있다. (중략)

• Journal of Korean Society of Environmental Engineers
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• v.33 no.11
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• pp.790-796
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• 2011

In this study, we measured the concentrations of volatile organic compounds (VOCs) in Shiwha area by using active and passive sampler. We did a comparative analysis of the characteristics of the active sampler and passive sampler. In the case of the passive sampler, the average TVOC concentration of the industrial area was 1.86 times higher than that of the residential area. In the case of the active sampler, the average TVOC concentration of the industrial area was 1.07 times higher than that of the residential area. When using the passive sampler, the concentration of VOCs in the industrial area was noted to be higher than the concentration found in the residential area. However, when we used the thermal desorption tube, the concentration of residential area was higher rather than that of industrial area in some substances such as trichloroethylene, toluene, ethylbenzene, and xylene. Toluene was a larger percentage of the overall BTEX ratio. In case of the passive sampler, the relative ratio of toluene, ethylbenzene, and xylene was higher in the industrial area than in the residential area. In contrast in case of the thermal desorption tube, the ratio of these substances was higher in the residential area rather than in the industrial area. The passive sampling in this study showed an appropriate method to analyze the temporal and spatial concentrations of air contaminants. This assessment would prove to be useful for its observance of standards or epidemical study.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.4
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• pp.390-399
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• 1999

Siliceous and calcareous deep-sea core sediments were collected by a multiple corer from the KODOS (Korea Deep Ocean Study) area, northeast equatorial Pacific, to compare vane shear strengths measured by two different apparatuses and in different places of on-board and on-land laboratories. The apparatuses were 1) a hand-held vane with four blades of $2.0{\times}2.0$ cm, and 2) a motorized shear vane system with four blades of $1.0{\times}0.88$ attached on a rotational viscometer. Depth profiles of shear strengths of core samples determined by the apparatuses do not show any consistent difference. Also, there is no consistent difference between shear strength values measured on-board and on-land laboratories after storing the core samples for three months in a cold room by a motorized shear vane system. However, there are considerable differences between depth profiles of shear strengths measured at four different points (holes) of a core sample. Moreover, significant differences among the profiles of different tube samples from a multiple corer within a sampling station were observed. Heterogeneity in physical properties of each depth and sediment column, possibly due to bioturbation and bottom current flows, is likely responsible for the differences in the geotechnical properties.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.1953-1956
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• 2008

본 연구에서는 금강의 하류부의 시간적 공간적 수질변화를 자세하게 분석하기 위하여 3차원 수리동역학 모델인 EFDC 와 비정상상태 수질모델인 WASP 7.2와 를 연계 적용하였다. 본 연구의 대상 구간은 금강하류 부중 대청댐 조절지 방류구 지점부터 공주의 정안천 유입 직전까지 총 48km의 구간이다. 하천의 수심별 수질은 일정하다고 가정하였으나 폭방향의 수질은 좌 중 우로 3개의 소구간으로 나누고 하천의 흐름 방향으로 나누어 전체적으로는 2차원적으로 구분하였다. 하천의 바닥 형상을 이용하여 모델 격자를 구성하였으며 수리모델은 건교부의 수위자료를 이용하여 보정하였고 수질자료는 환경부의 수질측정망 자료를 이용하여 보정하였다. 2차원 수리동역학-수질 연계모델링 결과, 대전 갑천이 유입되고 난 후의 청원지점에서 그리고 청주지역의 영향을 포함하는 미호천이 유입되고 난 연기 지점 그리고 본 연구의 최하류인 공주지점에서는 하천의 폭 방향으로 상당한 수질 차이가 있음을 확인하였다. 이는 대전 갑천 또는 청주 미호천 등이 유입된 이후 효과적으로 혼합되지 않는다는 것을 의미한다. 이는 해당지역의 수질시료 채취 위치에 따라 수질에 현격한 차이가 있을 수 있다는 것을 나타내며, 현재 환경부 수동측정망의 시료채취 방법을 고려하여 볼때 하천수질의 대표성을 나타낼 수 있는가 하는 문제의 차원에서 매우 심각하게 받아들여져야 할 것으로 생각된다. 한편, 현재 우리나라에서 시행되고 있는 오염총량관리제나 대부분의 환경영향평가에서는 하천의 폭 방향의 수질 차이에 대한 고려가 전무하며 이에 대한 전면적인 재검토가 시급하다고 판단된다.

• Analytical Science and Technology
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• v.13 no.6
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• pp.693-698
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• 2000

The object of this series of experiments was aimed for the systematic and long-term radioactivity monitoring through indirect search of C-14 concentration level changes in the natural conditions around the operating nuclear facilities. The result of environmental radioactivity level through tree-ring analysis is increased after operating nuclear facilities and such a level can be proved to relate power generation closely. The measured result of ${\delta}^{13}C$ through the treatment of cellulose can be showed the level -30‰. This figure is very different from one which is measured the -17‰ of air sample by passive air sampling and -8‰ of air sample by active air sampling. And these differences can be assumed as isotope fractionation by photosynthesis, but the problem is more study as needed.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.6
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• pp.373-381
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• 2012

An automatic flow and water quality monitoring system was applied to estimate pollutant loads to an urban stream during storm events in DTV (Daeduk Techno Valley), Daejeon, Korea. The monitoring system consists of rainfall gage, ultrasonic water level meter, water quality sensors for DO, temperature, pH, conductivity, turbidity and automatic water sampler for further laboratory analysis. All data are transmitted through on-line system and the monitoring system is designed to be controlled manually in the field and remotely from laboratory computer. Flow rates were verified with field measurements during storm events and showed good agreements. Automatic sampler was used to collect real time samples and analyzed for BOD, COD, TN, TP, SS and other pollutant concentrations in the laboratory. SWMM (Storm Water Management Model) urban watershed model was applied and calibrated using the observed flow and water quality data for the study area. While flow modeling results showed good agreement for all events, water quality modeling results showed variable levels of agreement. These results indicate that current options in the SWMM model to predict pollutant build up and wash-off effects are not sufficient to satisfy modeling of all the rainfall events under study and thus need further modification. This study showed the automatic monitoring system can be used to provide data to assist further refinement of modeling accuracy. This automatic stormwater monitoring and modeling system can be used to develop basin scale water quality management strategies of urban streams in storm events.