• 한국물환경학회지
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• 제29권2호
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• pp.165-169
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• 2013

Freshwater fish intake is a critical parameter for deriving water quality criteria and water quality standards for protection of human health based on human health risk assessment. Although the freshwater fish intake parameter should be accurate and representative of Korean fish consumption for the water quality criteria to be reliable, data are limited in Korea and have low reliability. In this study, Korean National Health and Nutrition Examination Survey data from 2008-2010 were analyzed to reevaluate freshwater fish consumption. Based on these results, an average consumption rate of 3.0 g/day per person, a $90^{th}$ percentile consumption rate of 0.0 g/day per person, an average consumption rate of 65.7 g/day per fish consumer, and a $90^{th}$ percentile consumption rate of 153.4 g/day per fish consumer were proposed for derivation of water quality criteria using a conservative approach and various exposure scenarios.

• 한국물환경학회지
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• 제21권5호
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• pp.470-476
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• 2005

The Korean Water Quality Index (K-WQI) was applied to the rivers located in the watershed of Daecheong Lake to assess the status of river water quality, and propose potential target constituents for better water quality management in the watershed. The estimated K-WQI value for each river was varied from 70 to 90, and Youngdongcheon showed the worst score while Mujunamdeachen showed the best score. The total nitrogen (TN) and total coliform bacteria were identified as the most significant constituents that degrade the K-WQI values in the rivers. The correlation coefficients (r) were determined between K-WQI and the delivered specific load ($kg/km^2/yr$) of BOD, TN, and TP to justify potential target constituents that have a great influence on the improvement of K-WQI values. The results showed that TN (r=-0.86) and TP (r=-0.85) have a strong negative relationships with K-WQI, but BOD have almost no effect. This implies that BOD, the surrogate parameter for organic pollutants, is no more a feasible water quality variable for the water quality management in the study site.

• 한국환경과학회지
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• 제20권5호
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• pp.575-580
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• 2011

This study characterized water quality of groundwater and purified water used for drinking water in 30 schools in Gyeongsangbukdo Province. The results of the study showed that 43% of groundwater and 45% of purified water were not suitable for drinking. Among them, microbial contaminations were the most serious problem. In raw groundwater, the exceeding rates of total colony counts was the highest in August (53.6%). Purified water samples showed higher rate of exceeding drinking water standard for total colony counts while showing lower rate of exceeding drinking water standard for total coliforms and fecal coliforms in March and August. Overall, proper managements for microbial contaminations are required for both groundwater and purified water. Furthermore, special attention should toward students not to drink water when groundwater or purified water exceeds the drinking water quality standard.

• 상하수도학회지
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• 제20권4호
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• pp.509-518
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• 2006

Although final water of domestic water treatment plants almost contains highly corrosive characteristics, the countermeasures for eliminating internal corrosion of pipeline system have not been conducted yet by controlling water quality in plants. The technologies of internal corrosion control are to control water quality parameters(pH, Alkalinity, and Calcium Hardness etc.) and to use corrosion inhibitor. Under the conditions of domestic water treatment, first of all, the technologies of adjusting water quality parameters has to be considered. Otherwise, The technology of using corrosion inhibitor is favorably thought to be applied with the technology of adjusting water quality parameters in accordance with the result of availability for water treatment process. Since the technology of adjusting water quality parameter influences on other water treatment processes, the guideline of water quality management to be apt for water quality characteristic is required to be estabilished. While the selection of proper chemicals and technologies is dependent upon the raw water characteristics and water treatment process, typically, the technology of $Ca(OH)_2$ & $CO_2$ additions is considered more effective than other technologies in order to adjust pH and Alkalinity, increase $Ca^{2+}$ and form $CaCO_3$ film

• 한국물환경학회지
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• 제29권6호
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• pp.762-776
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• 2013

Load duration curve was applied to determine important water quality parameter control term for improvement of Paldang lake water quality. Load duration curve was analyzed with long term data from 1985 to 2012 including water quality, flow rate and climate state of Paldang water environment. From the result of flow rate patterns of paldang lake, differences between high and low flow rate of each year showed tendency of increase because rainfall characteristics of paldang lake watershed were changed by climate exchange. Both of land use state of upper Paldang lake watershed and number of limit excess from load duration curve indicated that seasonal action related with land use such as agricultural fertilizer distribution in upper watershed affected Paldang lake water quality. So focused BOD (biological oxygen demand) management during spring season from march to June is required to control organic materials in Paldand lake. The main affecting factor of TOC (total organic carbon) increase in Paldang lake was initial rainfall after march. T-N (total nitrogen) kept increasing during research period, so enhancement of T-N standard is needed to T-N control. Initial rainfall and increase of temperature during spring season from March to June showed a positive correlation with TP (total phosphorus) and Chl-a, respectively.

• 한국정밀공학회지
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• 제14권1호
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• pp.101-107
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• 1997

Recently, as the raw water quality becomes to be polluted and the seasonal and local variation of water quality becomes to be severe, an exact control of coagulant dosing have been required in the water treat- ment plant. The amounts of coagulant is related to the raw water quality such as turbidity, alkalinity, water temperature, pH and edectrical conductivity. However the process of chemical reaction has not been clarified so far, so the dosing rate has been decided by jar-test, which is taken one or two hours. For the sake of this coagulant dosing control, fuzzy neural network to fuse fuzzy logic and neural network was proposed, and the scheme was applied to automatic determination of coagulant dosing rate. This controller can automatically identify the if-then rules and tune the membership functions by utilizing expert's cintrol data. It is shown that determination of coagulant dosing rate according to real time sensing of water quality is very effect.

• 대한토목학회논문집
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• 제26권3B호
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• pp.291-300
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• 2006

본 연구에서는 통계를 이용한 경안천유역의 최적 수질 측정망 구성이 제안된다. 분석을 위해서 필요한 수질 데이터는 QUAL2E 모형을 이용하여 모의하였으며, 경안천 유역의 2000년도 3월부터 11월까지의 월 평균자료를 이용하였다. QUAL2E 모형을 구축하는데 필요한 수리 매개변수는HEC-RAS모형을 이용하여 추정하였다. 수질매개변수의 경우 월평균 실측자료를 바탕으로 1차 신뢰성 분석(FORA)를 이용하여 민감도 분석을 실시하여 수질항목별로 민감하지 않은 매개변수를 제외한 후 보정이 이루어진다. QUAL2E 모형의 모의 결과를 바탕으로 크리깅 기법과 Branch and Boundary Method를 이용하여 평수량 일때와 갈수량 일때로 구분하여 관측지점의 개수와 위치가 결정된다. 또한 선정된 지점을 기준으로 proportional sampling method(비례표본추출법)를 이용하여 각각의 지점별 측정 빈도가 제시된다.

• 한국환경과학회지
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• 제7권4호
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• pp.433-440
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• 1998

This study was carried out to develop the stream water quality model for the intaking station of Kongju waterworks in the Keum River system. The monthly water quality(total nitrogen and total phosphorus) with periodicity and trend were forecasted by multiplicative ARIU models and then the applicability of the models was tested based on 7 years of the historical monthly water quality data at Kongju intaking strate. The parameter estimation was made with the monthly observed data. The last one year data was used to compare the forecasted water Quality by ARU model with the observed one. The models are ARIMA(2,0,0)$\times$(0,1,1)l2 for total nitrogen, ARIMA(0,1,1)x(0,1,1)l2 for total phosphorus. The forecasting results showed a good agreement with the observed data. It is implying the applicability of multiplicative ARIMA model for forecasting monthly water quality at the Kongju site.

• 한국수자원학회논문집
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• 제31권6호
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• pp.641-655
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• 1998

급속한 도시화의 영향에 따른 수자원 및 환경문제를 보다 효율적으로 해결하기 위하여 전문가 시스템의 개발 및 적용방안을 제안하였다. 이에 따라 도시유역의 유출 및 수질에 영향을 미치는 주요 매개변수들을 선별하고 민감도 분석 등을 통해 그 거동특성을 제시하였으며, 이러한 특성들을 바탕으로 효과적 매개변수 결정법칙 등을 제안하였다. CLIPS 6.0을 적용하여 ‘사실’과‘규칙’을 기본으로 한 전문가 시스템 ESPE를 개발하였으며, 이를 안양천 유역에 적용하였다. 결과적으로 유출관련 매개변수들의 추정결과를 매우 적용성이 높았으나, 수질관련 매개변수들의 추정결과는 그 모의과정의 복잡성과 의사결정 규칙의 부족 등으로 인하여 제시된 방법들에 대한 개선의 필요가 있음을 보여주었다.

• 한국물환경학회지
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• 제24권4호
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• pp.430-435
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• 2008

In order to design Non-point source management, the aspect of statistical features of the entire precipitation data should be focused since non-point source discharge is driven by continuous rainfall runoffs. 3-parameter mixed exponential probability density function is used to establish urban stormwater capture curve instead of previous single-parameter exponential PDF. Then, recent 10-year data in Busan are applied to establish the curve. The result shows that 3-parameter mixed PDF gives better resolution.