• 생태와환경
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• 제41권4호
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• pp.457-465
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• 2008

The purpose of the study was to evaluate spatial and temporal dynamics of nutrients (TN, TP), organic pollution (BOD, COD), and ionic dynamics (electrical conductivity, EC) in the North Han-River, South Han-River, and merged downriver using the dataset of $1998{\sim}2007$, obtained from the MEK (Ministry of Environment, Korea). Accord. ing to interannual nutrient analysis, TN varied slightly in the North Han-River and South Han-River, but decreased in the merged downriver along with BOD. Longitudinal analysis in the water quality showed that BOD, COD, and nutrients had linear decreasing trend along the main axis of headwater-to-downriver. Concentrations of TP and TN in the North Han-River averaged $26.97{\mu}g\;L^{-1}$, $1.696mg\;L^{-1}$, respectively, which were minimum in the three watersheds, followed by South Han-River and then the merged downriver in order. Ratios of TN:TP in the watersheds were >40 in all the sites, indicating that nitrogen may be enough for periphyton or phytoplankton growth and phosphorus may be limited partially. After the North Han-River water is merged with South Han-River, the concentrations of BOD, COD, TN, and TP were similar to the values of $S6{\sim}S7$, respectively or a little bit higher, but increased abruptly in Site M4 (Fig. 3). Thus, mean values of all the water quality parameters in the reach of $M4{\sim}M7$ sites were greater than any other sites. Seasonal data analysis indicated that BOD and EC in the downstream ($S3{\sim}S7$) was greater in the premonsoon than two seasons of the monsoon and postmonsoon, and no significant differences in BOD between the three seasons were found in the upstream ($S1{\sim}S2$). Empirical models of COD in the merged downriver was predicted ($R^2=0.87$, p>0.01, slope = 0.84, intercept = -1.28) well by EC. These results suggest that EC to be measured easily in the field may be used for estimations of nutrients and organic matter pollutions in the merged downriver and these linear models are cost-effective for the monitoring of the parameters.

• 해양환경안전학회지
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• 제29권6호
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• pp.697-703
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• 2023

최근 대기오염으로 인한 환경오염을 줄이고자 국제 산업계의 노력의 일환으로 국제해사기구(IMO)의 규제 발효등으로 이어지고 있다. IMO는 EEXI,EEDI,CII 등 선박에서 나오는 대기오염을 줄이기 위해 각종 규제를 발효시키고 선박에서 소모되는 전력을 줄여 에너지를 절약하는 방안을 추진하고 있다. 선박에서 사용되는 전력의 대부분은 전동기가 차지한다. 선박에 설치된 전동기 중 큰 부하를 차지하는 기관실 송풍기는 수요와 관계없이 정속운전으로 운전하기 때문에 주파수제어를 통한 에너지절감을 기대할 수 있다. 본 연구에서는 발전기의 과급기에 연소공기를 공급하는 발전기 송풍기의 전동기 주파수를 제어하여 에너지 절감에 대한 실효성을 입증하였다. 송풍기 주파수 입력에 따른 과급기출구 온도의 출력 데이터를 기반으로 시스템을 모델링하고, 과급기 출구온도를 목표값으로 하여 주파수를 제어하는 PI 제어계를 형성하여 과급기 설계기준 출구온도를 유지하면서 송풍기의 주파수 제어를 통해 연간 15,552kW 전력소모량을 절감하였다. 송풍기 팬 주파수 제어를 통한 에너지절감액의 유효성은 하계(4월~9월) 및 동계(3월~10월) 기간동안 검증하였으며 이를 토대로 실습선의 연간 6,091천원의 유류비 절약과 이산화탄소 8.5Ton, SOx 2.4kg, NOx 7.8kg의 대기오염물질 저감을 달성하였다.

• 한국습지학회지
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• 제18권2호
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• pp.194-200
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• 2016

도시화는 불투수면의 증가를 야기 시켜 물순환 왜곡, 도시열섬효과, 비점오염물질 유출 등의 다양한 문제를 유발한다. 이러한 환경적 영향을 저감하기 위하여 도시지역과 같은 개발 사업에서는 저영향개발(Low Impact Development, LID) 기법이 중요한 대안으로 제시되고 있다. LID 기술의 주요 기작은 토양, 여재, 미생물과 식물 상호간의 수문학적 및 환경학적 기능이 포함되며, 이 중에서 여재는 LID 시설에서의 토양 내 투수율과 저류율 확보에 있어 중요한 구성요소이다. 따라서 본 연구는 LID 시설에 다양하게 활용되고 있는 제올라이트(Zeolite), 우드칩(Woodchip), 바텀애쉬(Bottom ash), 바이오세라믹(Bioceramic) 등의 여재를 단층 또는 복층으로 구성하여 강우유출수내 오염물질 저감 효율을 평가하기 위하여 수행되었다. 실험에 사용된 모든 여재는 강우유출수에 포함된 입자상 물질과 중금속을 60% 이상 제거하는 것으로 나타났으며 여재층을 복층구조로 배치할 경우에 여재 입자간의 다양한 크기의 공극과 여재 내의 미세공극(micro-pores)을 충분히 확보할 수 있기에 입자상물질 및 중금속 저감에 효과적인 것으로 나타났다. 또한 유입수 내의 효과적인 중금속의 저감을 위해서는 중금속의 입자 및 용존성 함량비율에 따른 여재의 선정과 배치가 중요한 인자로 나타났다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1273-1273
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• 2001

The efficiency of the luminal fermentation process influences overall efficiency of luminal production, animal health and reproduction. Ruminant production systems have a significant impact on the global environment, as well. Animal wastes contribute to pollution of the environment as ammonia volatilized to the air and nitrate leached to ground water. Microbial protein synthesis in the rumen satisfies a large proportion of the protein requirements of animals. Quantifying the microbial synthesis is possible by using markers for lumen bacteria and protozoa such as nucleic acids, purine bases, some specific amino acids, or by isotopic $^{15}N,^{32}P,\;and\;^{35}S$ labelled feeds. All those methods require cannulated animals, they are time-consuming and some methods are very expensive as well. Many attempts have been made to find an alternative method for indirect measurement of microbial synthesis in intact animals. The present investigations aimed to assess possibilities of NIRS for prediction of purine nitrogen excretion and ruminal microbial nitrogen synthesis by NIR spectra of urine. Urine samples were collected from 12 growing sheep,6 of them male, and 6- female. The sheep were included in feeding experiment. The ration consisted of sorghum silage and protein supplements -70:30 on dry matter basis. The protein supplements were chosen to differ in protein degradability. The urine samples were collected daily in a vessel containing $60m{\ell}$ 10% sulphuric acid to reduce pH below 3 and diluted with tap water to 4 liters. Samples were stored in plastic bottles and frozen at $-20^{\circ}C$ until chemical and NIRS analysis. The urine samples were analyzed for purine derivates - allantoin, uric acid, xantine and hypoxantine content. Microbial nitrogen synthesis in the lumen was calculated according to Chen and Gomes, 1995. Transmittance urine spectra with sample thickness 1mm were obtained by NIR System 6500 spectrophotometer in the spectral range 1100-2500nm. The calibration was performed using ISI software and PLS regression, respectively. The following statistical results of NIRS calibration for prediction of purine derivatives and microbial protein synthesis were obtained.(Table Omitted). The result of estimation of purine nitrogen excretion and microbial protein synthesis by NIR spectra of urine showed accuracy, adequate for rapid evaluation of microbial protein synthesis for a large number of animals and different diets. The results indicate that the advantages of the NIRS technology can be extended into animal physiological studies. The fast and low cost NIRS analyses could be used with no significant loss of accuracy when microbial protein synthesis in the lumen and the microbial protein flow in the duodenum are to be assessed by NIRS.

• Asian Journal of Atmospheric Environment
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• 제6권4호
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• pp.268-274
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• 2012

To perform quick measurements of black carbon (BC) particles deposited on foliar surfaces of forest tree species, we investigated an optical method for measuring the amount of BC extracted from foliar surfaces and collected on quartz fiber filters. The seedlings of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica were exposed to submicron BC particles for one growing season (1 June to 7 December 2009). At the end of the growing season, the leaves or needles of the seedlings were harvested and washed with deionized water followed by washing with chloroform to extract the BC particles deposited on the foliar surfaces. The extracted BC particles were collected on a quartz fiber filter. The absorption spectrum of the filters was measured by spectrophotometer with an integrating sphere. To obtain the relationship between the absorbance of the filter and the amount of BC particles on the filter, the amount of BC particles on the filter was determined as that of elemental carbon (EC) measured by a thermal optical method. At wavelengths below 450 nm, the absorption spectrum of the filter showed absorption by biological substances, such as epicuticular wax, resulting in the low coefficient of determination ($R^2$) in the relationship between the amount of EC on the filter ($M_{EC}$, ${\mu}g\;C\;cm^{-2}$ filter area) and the absorbance of the filter. The intercept of the regression line between $M_{EC}$ and the absorbance of the filter at 580 nm ($A_{580}$) was closest to 0. There was a significant linear relationship between the $A_{580}$ and $M_{EC}$ ($R^2$=0.917, p<0.001), suggesting that the amount of BC particles collected on the filter can be predicted from the absorbance. This optical method might serve as a simple, fast and cost-effective technique for measuring the amount of BC on foliar surfaces.

• 한국해양환경ㆍ에너지학회지
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• 제17권1호
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• pp.1-7
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• 2014

본 논문에서는 석탄회 조립물을 이용한 저질개선 기술의 안전성 및 저질개선기구에 대해 논하고, 일본 카이타만 석탄회 조립물 피복구간에서의 저질개선효과에 대해 검토하였다. 석탄회 조립물의 중금속 농도 및 용출량은 일본의 환경기준을 만족하는 것으로 조사되었으며, 석탄회 조립물의 저질개선기능은 다음과 같이 요약할 수 있다. (1) 인산염 및 황화수소의 제거 (2) 산성 저질의 중화 (3) 투수성의 증가 및 이로 인한 환원상태 저질의 개선 (5) 지반강도의 증가 (6) 부착성 조류의 서식 기반. 일본 카이타만에서 실시한 현장실증실험 결과로부터 연안저질의 pH중화, 인산염 및 황화수소 농도 감소 등 석탄회 조립물의 저질개선효과가 검증되었으며, 이에 따른 저서생물의 증가가 확인되었다. 석탄회 조립물을 이용한 연안저질의 개선기술이 실용화 된다면 오염저질의 정화에 소요되는 비용의 절감은 물론 산업부산물인 석탄회의 재활용에 기여할 것으로 기대된다.

• 한국물환경학회지
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• 제27권4호
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• pp.425-432
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• 2011

To control non-point source pollution at a watershed scale, rainfall-runoff characteristics from forest watersheds should be investigated since the forest is the dominant land use in Korea. Long-term monitoring would be an ideal method. However, computer models have been utilized due to limitations in cost and labor in performing long-term monitoring at the watersheds. In this study, the Geo-spatial interface to the Water Erosion Prediction Project (GeoWEPP) model was evaluated for its runoff prediction from a coniferous forest dominant watersheds. The $R^2$ and the NSE for calibrated result comparisons were 0.77 and 0.63, validated result comparisons were 0.92, 0.89, respectively. These comparisons indicated that the GeoWEPP model can be used in evaluating rainfall-runoff characteristics. To estimate runoff changes from a coniferous forest watershed with various cover degree scenarios, ten cover degree scenarios (10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%) were run using the calibrated GeoWEPP model. It was found that runoff increases with decrease in cover degree. Runoff volume was the highest ($206,218.66m^3$) at 10% cover degree, whereas the lowest ($134,074.58m^3$) at 100% cover degree due to changes in evapotranspiration under various cover degrees at the forest. As shown in this study, GeoWEPP model could be efficiently used to investigate runoff characteristics from the coniferous forest watershed and effects of various cover degree scenarios on runoff generation.

• 한국방재학회 논문집
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• 제8권6호
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• pp.149-153
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• 2008

개발에 따른 수질오염을 최소화하기 위해서는 사업 전 후에 발생하는 오염량을 정량적으로 산정하여 관리할 필요가 있다. 점 오염원(point source)은 발생대상과 규모가 확정적이므로 법률적으로 강화된 기준에 의하여 충분한 대책을 수립할 수 있다. 이에 반해 비점오염원(non-point source)은 점오염원을 제외한 모든 오염원으로 발생기구나 전파경로에 대한 관리가 점오염원의 경우보다는 어렵다. 기존의 비점오염원 관리를 위한 강우량의 규모결정은 단순히 손실우량을 가정하여 이보다 큰 강우량을 이용하였으나 이는 연간 발생횟수나 지속시간에 대한 항은 거의 고려하지 못하는 실정이다. 이를 해결하기 위해서는 적정 설계강우량의 크기를 연간 발생횟수나 지속시간을 고려하여 결정하고 초기손실량, 유출률, 연간강우량, 연간강우횟수에 대한 적절한 민감도 분석(sensitivity analysis)이 동시에 수행 되어야한다. 본 연구에서는 평상시 강우의 발생특성에 대한 해석 기법연구와 해석적 확률기법(analytical probabilistic method)을 도입하고 공학적으로 합리적인 정량적 산정방법 및 최적환경용량 산정기법에 대하여 제시하여 실제 개발사업에서 합리적인 비점오염원 처리시설의 용량 및 효율을 결정할 수 있도록 하여 최적의 유역관리가 가능하도록 제안하였으며, 이를 위한 실증적 적용결과 분석을 위하여 유역자체개발에 의한 택지개발사례를 검토하였다. 앞으로도 개발은 계속 이루어질 수밖에 없으며, 개발에 따른 영향을 최소화하여 지속가능한 개발을 이루어야 한다. 특히 수자원의 이용에서 유역자체 개발과 더불어 수자원자체 개발에서도 점오염원의 관리만으로는 수질관리가 불가능한 것으로 판단되었다. 비점 오염원의 관리 시스템은 지속적으로 개발되고 있으나 정량적인 환경용량 산정 없이 편의적 접근이 시도되는 현실에 비추어 보다 공학적이고 정확한 판단이 필요한 시점이다. 이러한 일련의 기작으로 개발에 의하여 추가 발생되는 비점오염원의 양을 정량적으로 산정하여 자연상태보다 적극적인 대책을 수립하면 개발에 따른 오염원의 최소화뿐만 아니라 자연상태보다 효율적인 유지관리가 가능하다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1997년도 추계 국제학술심포지움 논문집
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• pp.3-31
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• 1997

Water has always played a significant role in the lives of people. In urbanised Rome, with its million people. sophisticated supply systems developed and then fled with the empire. only to be rediscovered later But it was the industrial Revolution commencing in the eighteenth century that ushered in major paradigm shifts In use and altitudes towards water. Rapid and concentrated urbanisation brought problems of expanded demands for drinking supplies, waste management and disease. The strategy of using water from local streams, springs and village wells collapsed under the onslaughts of rising urban demands and pollution due to poor waste disposal practices. Expanding travel (railways. and steamships) aided the spread of disease. In England. public health crises peaks, related to water-borne typhoid and the three major cholera outbreaks occurred in the late eighteenth and early nineteenth century respectively. Technological, engineering and institutional responses were successful in solving the public health problem. it is generally accepted that the putting of water into pipe networks both for a clean drinking supply, as well as using it as a transport medium for removal of human and other wastes, played a significant role in towering death rates due to waterborne diseases such as cholera and typhoid towards the end of the nineteenth century. Today, similar principles apply. A recent World Bank report Indicates that there can be upto 76％ reduction in illness when major water and sanitation improvements occur in developing countries. Water management, technology and thinking in Australia were relatively stable in the twentieth century up to the mid to late 1970s. Groundwater sources were investigated and developed for towns and agriculture. Dams were built, and pipe networks extended both for supply and waste water management. The management paradigms in Australia were essentially extensions of European strategies with the minor adaptions due to climate and hydrogeology. During the 1970s and 1980s in Australia, it was realised increasingly that a knowledge of groundwater and hydrogeological processes were critical to pollution prevention, the development of sound waste management and the problems of salinity. Many millions of dollars have been both saved and generated as a consequence. This is especially in relation to domestic waste management and the disposal of aluminium refinery waste in New South Wales. Major institutional changes in public sector water management are occurring in Australia. Upheveals and change have now reached ail states in Australia with various approaches being followed. Market thinking, corporatisation, privatisation, internationalisation, downsizing and environmental pressures are all playing their role in this paradigm shift. One casualty of this turmoil is the progressive erosion of the public sector skillbase and this may become a serious issue should a public health crisis occur such as a water borne disease. Such crises have arisen over recent times. A complete rethink of the urban water cycle is going on right now in Australia both at the State and Federal level. We are on the threshold of significant change in how we use and manage water, both as a supply and a waste transporter in Urban environments especially. Substantial replacement of the pipe system will be needed in 25 to 30 years time and this will cost billions of dollars. The competition for water between imgation needs and environmental requirements in Australia and overseas will continue to be an issue in rural areas. This will be especially heightened by the rising demand for irrigation produced food as the world's population grows. Rapid urbanisation and industrialisation in the emerging S.E Asian countries are currently producing considerable demands for water management skills and Infrastructure development. This trend e expected to grow. There are also severe water shortages in the Middle East to such an extent that wars may be fought over water issues. Environmental public health crises and shortages will help drive the trends.

• 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.