• 상하수도학회지
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• 제20권3호
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• pp.347-355
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• 2006

Anyang Stream including its main branch is the biggest branch stream of Han River in Korea. The geological and geomorphological characteristics were investigated to the affected area of Anyang Stream, in which rainfall characteristic was analyzed. The water quality surveyed that the analysis of water pollution used to biotic index and biological water pollution. The rainfall pattern in this area was like to that of typical Korea, but the rate of trigger and runoff during summer season(June~August) is more higher than mean of Korea. Before 2003, a dried stream is severe status, which was due to abundant runoff, but this status are improved. After 1997, water quality of stream is recovering status such as water pollution of stream steeply decreased. Especially after 2003, this trend is more quickly improved. Although, owing to the increasing of a T-N and SS at upstream wastewater were due to bad collection of industrial factories, livestock's and mans living, the water quality worsted at upstream. Water quality in total section of main stream was severely contaminated that water-quality limit is 5 with polysaprobic by water self-purification. That of main branch was 1~3limits with ${\alpha}$- and ${\beta}$-mesosaprobic in Anyang city area, But water quality in all area about another branch of Anyang stream except Anyang city area was almost under of 3 grades. Though trying of Anyang city for recover movement(completion of 2nd Sewage Treatment Plant and Water supply pipe system) on Anyang stream, water pollution states of upper branch in Anyang stream was not better than its of 2002 because it may be difference of control area on other cities.

• 한국물환경학회지
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• 제28권1호
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• pp.26-37
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• 2012

Multi-dimensional hydrodynamic and water quality models are widely used to simulate the physical and biogeochemical processes in the surface water systems such as reservoirs and estuaries. Most of the models have adopted the Eulerian grid modeling framework, mainly because it can reasonably simulate physical dynamics and chemical species concentrations throughout the entire model domain. Determining the optimum grid cell size is important when using the Eulerian grid-based three-dimensional water quality models because the characteristics of species are assumed uniform in each of the grid cells and chemical species are represented by concentration (mass per volume). The objective of this study was to examine the effect of grid-size of a three dimensional hydrodynamic and water quality model (EFDC) on hydrodynamics and mass transport in the Saemangeum Reservoir. Three grid resolutions, respectively representing coarse (CG), medium (MG), and fine (FG) grid cell sizes, were used for a sensitivity analysis. The simulation results of numerical tracer showed that the grid resolution affects on the flow path, mass transport, and mixing zone of upstream inflow, and results in a bias of temporal and spatial distribution of the tracer. With the CG, in particular, the model overestimates diffusion in the mixing zone, and fails to identify the gradient of concentrations between the inflow and the ambient water.

• 환경영향평가
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• 제30권2호
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• pp.75-88
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• 2021

본 연구에서는 금강 수계의 자동측정망 중 6개 지점을 선정하고, 이와 동일하거나 인근에 위치해 있는 수질측정망 지점을 대상으로 두 지점의 수질특성 파악하고 통계 분석을 통하여 상관성을 평가하였다. 또한, 수질 분석결과를 활용하여 수질 지수로 변환하고 등급으로 표현해 비교하였다. 연구에 필요한 자료는 최근 4년간(2016-2019)의 국가물환경측정망 데이터를 활용하였으며 수온, pH, EC, DO, TOC, TN, TP를 평가항목으로 선정하였다. 수질 분석 결과, 자동측정망과 수질측정망의 수질농도는 일부 측정값의 차이는 보였지만 대부분 지점에서 일정한 비로 변동하는 경향을 보였다. 항목 간 상관분석결과 수온, EC, DO 항목은 측정망간 상관성이 매우 높았고, TOC, TN, TP 항목은 기본항목에 비해 낮은 상관성을 보였으나 일부 측정망을 제외하고 0.7 이상(상관계수 r)의 높은 상관관계를 나타냈다. 수질 지수 분석결과 자동측정망 수질지수와 수질측정망 수질지수가 비슷한 경향을 보이는 것으로 평가되었으며, 두 결과 모두 하류로 갈수록 지수점수는 낮아져 오염도가 증가되고 있음을 쉽게 파악할 수 있었다.

• 한국물환경학회지
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• 제30권3호
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• pp.283-291
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• 2014

To study the distribution characteristics of diatom communities in relation to the gradient of water quality and land-use, water samples and epilithic diatoms were collected from 90 sites including mainstream and tributaries, in the Geum River System (GRS) during no rainfall, May 2011. Of 239 taxa identified, Achnanthes convergens and Cymbella minuta were dominated over all the sites. Cluster analysis on the GRS divided into three groups. Group 1 (G1) is the mountainous upstream, a relatively good water quality, and mainly consisted of saproxenous species. Group 2 (G2) is the urban sites, polluted (high in electric conductivity, total phosphate and soluble reactive phosphorus), and saproxenous and common species. Group 3 (G3) is the agriculture sites, and polluted (turbidity, total nitrogen, nitrate), and saprophilous species. There were some discrepancies between abiotic and biotic variables in GRS; biologically similar between G1 and G2, but abiotically similar between G2 and G3. These differences may attribute to not only physiological characteristics of diatom cells, but complicate relationships between microhabitat and water quality. Thus, an urgent development of generalized or standardized methods to diminish the differences between epilithic diatom community and environments is advent.

• 한국식생활문화학회지
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• 제32권2호
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• pp.135-143
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• 2017

This study evaluated the quality characteristics of semi-dried noodles prepared with different water contents (wet noodles; 32, 24, 22, 20%, dry noodles; 12%). The drying process was carried out in a drying chamber at $13{\sim}18^{\circ}C$ temperature and 75~95% humidity. The proximate composition of Korean wheat flour was as follows: water $22.1{\pm}3.64%$, protein $8.6{\pm}0.13%$, fat $1.3{\pm}0.10%$, ash $0.7{\pm}0.02%$, carbohydrates $67.3{\pm}0.10%$. As water contents decreased, both L and b values significantly decreased before cooking of noodles, whereas L, a, and b values were not significantly different after cooking of noodles. Weight, water absorption, and volume of cooked noodles significantly increased as water content decreased, whereas turbidity of soup was not significantly different. Cutting hardness before cooking of noodles significantly increased as water content decreased. Sections of noodles after cooking by SEM (scanning electron microscopy) showed roughness and fewer round starch particles as water content decreased. For overall preferences according to the sensory evaluation, noodles prepared with different water contents were not significantly different. According to the results, semidried noodles have development potential to complement the disadvantages of both wet noodles and dry noodles.

• 생명과학회지
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• 제22권8호
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• pp.1041-1045
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• 2012

낙동강 유지용수가 공급되고 있는 온천천을 대상으로 2009년 10월부터 2010년 10월까지 수질 및 생물학적 인자변화를 조사하였다. 조사결과 온천천은 BOD, TN, TP 그리고 중금속 농도가 낙동강 유지용수가 공급되기 이전인 2005년에 비해 뚜렷하게 감소한 것으로 나타났으며, 특히 BOD 평균농도가 2.0 mg/l로 모든 지점이 2급수를 유지하였다. 또한 온천천 수중에 존재하는 플랑크톤과 저서성 대형 무척추동물의 종 및 개체수도 증가한 것으로 조사되었다. 결론적으로 낙동강 유지용수가 공급된 이후에 온천천은 수질 및 생물변화와 같은 물 환경인자가 상당히 개선되었음을 알 수 있었다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2017년도 학술발표회
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• pp.545-545
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• 2017

본 연구에서는 낙동강 유역 본류와 주요 지천의 오염총량관리대상지점을 대상으로 수질 현황과 시공간적 수질특성을 분석을 위해 하수처리장과 주요 지천의 유입으로 인한 낙동강 본류 수질의 공간적 변화양상과 계절별 하천유량의 변화에 따른 수질특성을 분석하였다. 자료구축을 위해 국가수자원관리종합정보시스템(WAMIS)의 하천 공간 지형 자료, 국립환경과학원의 수질관측지점 공간지형자료, 그리고 전국오염원조사 자료의 하수처리장 공간 지형 자료를 이용하였다. 수질자료는 국립환경과학원 물환경정보시스템에서 제공하는 8일 간격 수질자료를 2004년부터 2015년까지 수집하여 이용하였고, 수집한 자료는 갈수기와 전체 기간에 대해 수질 항목(유량, BOD, T-N, T-P)별로 산술 평균하였다. 하수처리장 32개소의 방류수질 자료는 국립환경과학원의 전국오염원조사 자료를 2012년부터 2015년까지 수집하여 갈수기인 봄, 가을철에 대해 수질항목 별로 산술평균하였다.

• 환경위생공학
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• 제7권1호
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• pp.35-44
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• 1992

This paper included the preventive measures and the prospect of lake eutrophication in korea. All pollution control techniques must be applied after the characteristics of the lakes are surveyed sufficlenty, Most of Korean lakes are the large man-made ones and their characteristics are different from those of natural ones in foreign nation. Some of many techniques for natural lakes can be applied in our lakes also, others must be revised. Lake water quality can be ameliorated only by systematic researches and technologies because lake ecosystem is very complicated. It is impossible to improve water quality with fragmentary and shortterm projects.

• 한국물환경학회지
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• 제24권6호
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• pp.701-708
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• 2008

As a countermeasure for reduction of corrosion in the delivery and distribution pipes used for tap water, materials for the pipelines in-houses and the effect of water quality on corrosivity of water pipelines were investigated in the distribution system of Han river. As the corrosion index at 6 water purification facilities of Han river, average Langelier Saturation Index (LI) of raw and finished water were -1.0 and -1.4 respectively and average Larson Index (LR) were 9.5 and 9.9, respectively. And also corrosion potential showed corrosivity in finished water (-431~-462 mV) as well as raw water (-426~-447 mV). This results indicate that tap water quality of han river have corrosivity. To understand the corrosivity effect in pipe material used for premise distribution system, water quality of stagnant tap water and tap water were analyzed and the differences between them were calculated. The difference concentration of iron, copper and zinc were $12.9{\mu}g/L$, $31.0{\mu}g/L$ and $45.0{\mu}g/L$ respectively in galvanized steel pipe for use more than 15 years and showed highest concentration. As a result, the control to corrosivity in the water pipelines, corrosivity control treatment in the water purification system can be applied. In advance it is necessary to monitor corrosivity of water quality using corrosive index because corrosivity may differ from the seasonal and regional characteristics and water chemicals dosage. For the future the guideline for corrosion index have to be established.

• 한국식품조리과학회지
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• 제30권6호
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• pp.695-703
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• 2014

Daebong persimmon puree (DPP) prepared from removing the astringency of persimmon was used as a substitute for water when making the dough of white pan bread using domestic wheat flour, and the resulting, quality characteristics were investigated. The moisture content of DPP was 96.69%, and the dough was made by various levels of substitution of DPP for water (0, 10, 30, 50 and 100%). During fermentation, the expansion power of the dough decreased with increasing DPP levels (p<0.05). The volume, specific volume, baking loss, and the L and ${\Delta}E$ values of the crust and crumb of the breads also decreased with increasing DPP levels. The hardness and chewiness of the bread containing 100% DPP (without water) showed the highest values, but the springiness, cohesiveness and resilience showed the opposite trends. In the difference tests, all attributes except air cell uniformity were significantly different (p<0.05). Bread made with 100% substitution of DPP for water achieved the highest scores for flavor, taste and overall acceptability.