• Title/Summary/Keyword: Water quality comparison

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A Comparison Between Reduction Methods for BOD Loadings to Achieve Water Quality Standards at the End of the Yeongsan River (영산강 하류부의 목표수질 달성을 위한 BOD 부하량 삭감방법의 비교)

  • 황대호;정효준;이홍근
    • Journal of Environmental Health Sciences
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    • v.27 no.2
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    • pp.119-126
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    • 2001
  • The key point in establishing water quality management measures is how to decide the load reduction for pollution sources. This study was performed to compare reduction methods for BOD loadings to achieve water quality standards at the end of the Yeongsan river. The target year is 2006 and 2011 and reduction methods are uniform treatment and treatment by influence rate. Using QUAL2E model, the study was performed under the conditions of establishing and non-establishing the publicly owned treatment works(POTWs). Uniform treatment which allocate the same reduction rate to pollution sources showed that all streams into the river should be applied for the reduction. However, treatment by influence rate which allocate the reduction rate by the order of influence rate showed that achieving target quality might be possible with a few streams for the reduction. But total amount of load reduction of streams was not significantly different from two methods.

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Improvement of Channel Water Quality Module in SWAT (SWAT 모형의 하도 수질 모듈의 개선)

  • Kim, Nam-Won;Shin, Ah-Hyun
    • Journal of Korean Society on Water Environment
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    • v.25 no.6
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    • pp.902-909
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    • 2009
  • With various reservoirs, dams and reduction of water velocity in downstream, rivers in Korea often have characteristics of accumulation of pollutants. Therefore, the main focus of water quality modeling in Korea needs to be shifted from DO to algae and organic matter. Moreover the structures of water quality models should be modified to have capability of simulating BOD which is a key factor of total water pollution load management in Korea as laboratory experiment BOD (Bottle $BOD_5$). In the SWAT model which is one of the widely used water quality models in Korea, the channel water quality module is using main algorithm of the QUAL2E model which has limitations in simulating algae, organic matter and Bottle BOD5 etc. To overcome this hindrance, in this study, the improved channel water quality module of the SWAT model (Q-SWAT) was proposed by linking the algorithms of the QUAL-NIER model which was developed based on the QUAL2E model to the SWAT model. The algorithms estimating the increase of internal organic matter by fractionization algal metabolism process and calculating Bottle $BOD_5$ were added and the results of proposed model were compared to those of the original SWAT model. The results of comparison test are showing that more accurate BOD values can be obtained with the Q-SWAT model and it is anticipated that the Q-SWAT model can be used as an effective tool of decision support through the water quality simulation and long term pollution source analysis.

A Comparison of Controlled and Uncontrolled Hypertension Groups Regarding Comprehensive Diagnosis of Qi Blood Water and Quality of Life (고혈압 환자에서 혈압 조절 여부에 따른 기혈수(氣血水) 변증(辨證)과 삶의 질 비교)

  • Choi, In-Young;Han, Chang-Ho;Choi, Dong-Jun;Jung, Seung-Hyun;Shin, Gil-Jo
    • The Journal of Internal Korean Medicine
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    • v.31 no.4
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    • pp.880-891
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    • 2010
  • This study is about a comparison of controlled and uncontrolled hypertension groups regarding comprehensive diagnosis of Qi blood water and quality of life. We surveyed "controlled and uncontrolled hypertension patients" using questionnaires for comprehensive diagnosis of Qi blood water, SF-36 and HTN QoL (Measurement Scale for the quality of life in hypertensive patients). There was no difference in comprehensive diagnosis of Qi blood water between the controlled and uncontrolled hypertension groups. Within the controlled hypertension group, the patients diagnosed with a Qi deficiency, Qi stagnation, Qi counterflow, blood deficiency, and water retention received lower total scores in SF-36 and HTN QoL than in undiagnosed patients. Within the uncontrolled hypertension group, the patients diagnosed with Qi deficiency, blood deficiency, and water retention got lower total scores in SF-36 and HTN QoL than in undiagnosed patients. These results were statistically significant. These results are insufficient that we and use comprehensive diagnosis of Qi blood water for a diagnosis tool of hypertension. But if we have better studies that make up for weak points, these results will help to make a diagnosis tool for hypertension.

Comparison between Neural Network and Conventional Statistical Analysis Methods for Estimation of Water Quality Using Remote Sensing (원격탐사를 이용한 수질평가시의 인공신경망에 의한 분석과 기존의 회귀분석과의 비교)

  • 임정호;정종철
    • Korean Journal of Remote Sensing
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    • v.15 no.2
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    • pp.107-117
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    • 1999
  • A comparison of a neural network approach with the conventional statistical methods, multiple regression and band ratio analyses, for the estimation of water quality parameters in presented in this paper. The Landsat TM image of Lake Daechung acquired on March 18, 1996 and the thirty in-situ sampling data sets measured during the satellite overpass were used for the comparison. We employed a three-layered and feedforward network trained by backpropagation algorithm. A cross validation was applied because of the small number of training pairs available for this study. The neural network showed much more successful performance than the conventional statistical analyses, although the results of the conventional statistical analyses were significant. The superiority of a neural network to statistical methods in estimating water quality parameters is strictly because the neural network modeled non-linear behaviors of data sets much better.

Comparison of Changes in Upstream and Downstream Water Quality of Tributary Rivers: Gyeseong-stream and Hwapo-stream in Nakdongmiryang Watershed (지류하천의 상·하류 수질변화 비교: 낙동밀양 중권역 내 계성천 화포천을 대상으로)

  • Shim, Kyuhyun;Kim, Gyeonghoon;Kim, Seongmin;Kim, Youngseok;Kim, Jin-pil
    • Journal of Korean Society on Water Environment
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    • v.36 no.5
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    • pp.445-452
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    • 2020
  • Tributary is a part of life space for people and a very important place that accommodates rest recreation and other daily activities. absolutely insufficient basic data about water quality and flow rate are available for basin management. Efficient water and basin management systems, which are also supported by local residents can be established by securing such basic data of major tributaries in the Nakdong river system. In this study, the fluctuation characteristics of upstream and downstream water pollution levels were compared using the measurement results of the water environment measurement network and the tributary monitoring project for the gyeseong-stream and Hwapo-stream in the Nakdong-miryang watershed. In 2017, when water pollution is the highest, it was confirmed that the annual average rainfall was the lowest. Although the upstream and downstream water quality tendencies of the Gyeseong-stream are similar, the water quality concentrations of the Gyeseong-stream are relatively different. But although the Hwapo stream has various causes of pollution, there was not much difference in the level of pollution between the upper and lower streams. In addition, both rivers need the ability to purify rivers by securing sufficient water for river maintenance, and if the correlation between water quality items can be inferred through continuous monitoring of tributaries where the aspect of water quality change is unclear, water quality management Determined to be efficient operation.

Comparison of Four Different Ordination Methods for Patterning Water Quality of Agricultural Reservoirs

  • Bae, Mi-Jung;Kwon, Yong-Su;Hwang, Soon-Jin;Park, Young-Seuk
    • Korean Journal of Ecology and Environment
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    • v.41 no.spc
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    • pp.1-10
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    • 2008
  • We patterned water quality of agricultural reservoirs according to the differences of six physico-chemical environmental factors (TN, TP, DO, BOD, COD, and SS) using four different ordination methods: Principal Components Analysis (PCA), Detrended Correspondence Analysis (DCA), Nonmetric Multidimensional Scaling (NMS), and Isometric Feature Mapping (Isomap). The data set was obtained from the water quality monitoring networks operated by the Ministry of Agriculture and Forestry and the Ministry of Environments. Chlorophyll-${\alpha}$ displayed the highest correlation with COD, followed by TP, BOD, SS, and TN (p<0.01), while negatively correlated with altitude and bank height of the reservoirs (p<0.01). Although four different ordination methods similarly patterned the reservoirs according to the gradient of nutrient concentration, PCA and NMS appeared to be the most efficient methods to pattern water quality of reservoirs based on the explanation power. Considering variable scores in the ordination map, the concentration of nutrients was positively correlated with Chl-${\alpha}$, while negatively correlated with altitude and bank height. These ordination methods may help to pattern agricultural reservoirs according to their water quality characteristics.

A Study of Comparison of outflow characteristics of pollutants by rainfall event of forest area near Juam lake basin (주암호 유역의 강우사상에 따른 오염물질의 유출특성)

  • Kim, Nam-Joung;Shin, Dae-Yewn
    • Journal of environmental and Sanitary engineering
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    • v.22 no.4
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    • pp.87-104
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    • 2007
  • The objective of this study is to estimate the load of pollutants caused from the forest area among non-point pollutants within the Juam lake. The surveyed forest area was classified into broad-leaved, conifer, mixed and herbage area by forest tree type. Water quality and flux were investigated under rainfall and non-rainfall, respectively. Then, pollutant loading was evaluated by using the values of unit pollutant loading factor of each point and area of forest zone. Water quality analysis results of runoff by forest tree types were as follows. - Annual BOD, $COD_{Mn}\;and\;COD_{Cr}$ concentration of runoff in conifer area was high, and particle and biological recalcitrant compounds were flowed highly. - SS, T-N and T-P concentration was high in runoff from broad-leaved area, and biological degradable compounds was flowed. - Water quality of water from valley was maintained good under non-rainfall and could be utilized as fresh drinking water. Through water quality standard investigation, a countermeasure establishment was necessary to secure a good quality of drinking water - BOD, $COD_{Mn},\;and\;COD_{Cr}$ concentration of Bo-sung river was higher 1.5 times than other 2 streams, and because of high T-N, and T-P concentration in Songgwang stream, the management for this was necessary.

Comparison of Steady and Unsteady Water Quality Model (정상 및 비정상상태 하천수질모형의 비교)

  • Ko, Ick-Hwan;Noh, Joon-Woo;Kim, Young-Do
    • Journal of Korea Water Resources Association
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    • v.38 no.6 s.155
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    • pp.505-515
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    • 2005
  • Two representative river water quality models have been compared in this paper. The steady water quality model, QUAL2E, and the unsteady model, CE-QUAL-RIV1, have been chosen for comparative simulations. Under same reaction coefficients and boundary conditions, the water quality of the Geum river below the Daechung dam has been simulated using two different models, and the water quality equations are compared each other. Since basic model algorithm is very close, the input data required for model run is very similar. Upon the simulation under steady condition, the results of two models show very good agreement especially for BOD, DO, and $NH_3-N$, while the results of specific constituent such as dissolved P is quite different. As a result, dominant water quality parameters to compute each corresponding water quality variables are summarized and tablized through the sensitivity analysis.

Quality Control to Improve Reliability of Automatic Water Quality Data (수질자동측정망 자료의 신뢰성 제고를 위한 정도관리)

  • Lim, Byung-Jin;Hong, Eun-Young;Kim, Hyun-Ook
    • Korean Journal of Ecology and Environment
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    • v.43 no.2
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    • pp.338-344
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    • 2010
  • The automatic water quality monitoring system (AWQMS) have been installed to immediately response to any pollution incident. It also make it possible to conduct the task efficiently regarding water quality control. The purpose of this study is to enhance reliability by securing accuracy of automatic water quality data through quality assessment (QA) for temperature, pH, dissolved oxygen (DO), electric conductivity (EC), total organic carbon (TOC). The result of comparison between manual and automatic data, relative accuracy of general items (temperature, pH, EC, DO) and TOC were mostly satisfied with guideline (i.e. less than 20%). On the other hand, relative accuracy of DO between sampling site and housing site was somewhat against the guideline. The contamination by attaching algae and microorganism in the pipeline is considered as main cause. After backwashing the pipeline, DO concentration was increased up to 53%. Therefore, pipeline management is recognizable as important thing to secure reliability of water quality data.