• 상하수도학회지
• /
• 제29권4호
• /
• pp.469-479
• /
• 2015

This study have been conducted to analyze the feasibility of establishing Contamination Warning System(CWS) that is capable of monitoring early natural or intentional water quality accidents, and providing active and quick responses for domestic C_water supply system. In order to evaluate the water quality data set, pH, turbidity and free residual chlorine concentration data were collected and each statistical value(mean, variation, range) was calculated, then the seasonal variability of those were analyzed using the independent t-test. From the results of analyzing the distribution of outliers in the measurement data using a high-pass filter, it could be confirmed that a lot of lower outliers appeared due to data missing. In addition, linear filter model based on autoregressive model(AR(1) and AR(2)) was applied for the state estimation of each water quality data set. From the results of analyzing the variability of the autocorrelation coefficient structure according to the change of window size(6hours~48hours), at least the window size longer than 12hours should be necessary for estimating the state of water quality data satisfactorily.

• 한국물환경학회지
• /
• 제22권4호
• /
• pp.666-671
• /
• 2006

Effects of a rainfall event (July 28, 2005) on the hydrochemical characteristics of the Jungrang river, the biggest tributary of the Han river, was investigated. Significant spatial variations in the hydrochemical characteristics were observed. At JR2 location, concentrations of T-N and T-P were relatively low indicating occurrence of active oxidation in the stepped drop structure. At JR3 location, concentrations of Na, K, Cl, $NH_4-N$ and EC were elevated suggesting increased discharge from the nearby waste-water treatment plant and tributaries. The rain event diluted major dissolved ion concentrations in the river by 12~52%. The $NO_3-N$ levels were preserved during the rain then increased about twofold after rainfall, suggesting increased discharge of nitrate-contaminated groundwater. Heavy metals including Cd, Co, Cr, Cu and Pb were not detected in all water samples and the leachates from surface sediment samples. Concentrations of Fe, Mn, Al and Zn were below the Korean Drinking Water Guideline. Results of this study suggested that establishment of water-quality monitoring protocols describing temporal and spatial variations in parameters sensitive to rainfall events, relatively steady factors, and contaminant sources is required.

• 환경생물
• /
• 제19권2호
• /
• pp.119-128
• /
• 2001

본 연구는 1999년 9월부터 2000련 8월까지 1년간 강원도 평창군 소재 평창강 일대의 15개 조사지점을 대상으로 계절별로 저서성 대형무척추동물을 채집, 분류, 동정하고 현지 수질을 생태학적으로 평가한 것이다. 총 4문 4강 10목 31과 77속 109종이 채집되었으며, 조사지점 중 진부면 간평리에서 53종(48.0%)이 채집되어 가장 많은 종들이 출현하였고 마하리와 창동리에서도 각각 51종(46.7%), 50종(45.8%)이 채집되었다. 그러나 수하리 스키장 하부에서는 13종(11.9%)이 채집되어 전 조사지점 중 가장 적은 종들이 출현되었다. 한편 조사지점 전역에 걸쳐 하루살이류가 가장 풍부하게 서식하고 있었으며, 우점종에 있어서는 하루살이류(ephemeropterans)와 날도래류(trichopterans)가 대부분을 차지하고 있었다. 종다양도 지수치(H')는 개수리 지역이 3.67로 가장 높고, 방림리가 1.38으로 가장 낮았다. TBI 지수치는 대다수 지점이 9 이상으로서 청정 지역으로 간주되나 수하리에서는 4-5로 낮은 수치를 나타내었다. BMWP 지수치에서는 대부분 지점이 7.0 이상이나 수하리 지역은 3.5-5.2로 역시 가장 낮은 수치를 나타내었다. BI 지수에서도 수하리 지역을 제외하고 모두 1.5 이하의 낮은 수치로 청정한 수역으로 판정되었다.

• 한국농공학회지
• /
• 제39권2호
• /
• pp.113-123
• /
• 1997

This study was initiated to build runoff plots, install soil and water quality monitoring systems and collect background data from the plots and neighboring soils as the 1st year study of a 5 year project to assess soil quality and develop the management practices for environmentally sound agriculture in mountainous soils. Eleven $3{\times}15m$ runoff plots and monitoring systems were installed at a field of National Alpine Agricultural Experiment Station to monitor soil quality and discharge of nonpoint source pollutants. Corn and potato were cultivated under different fertilizer, tillage and residue cover treatments. The soil has a single-layered cluster structure that has a relatively good hydrologic properties and can adsorb a large amount of nutrient. Concentrations of T-N, $NH_4$-N, and $NO_3$-N of surface soil sampled in the winter were relatively high. Runoff quality in the winter and thawing season in the spring was largely dependent on surface freezing, snow accumulation, temperature, surface thawing depth and so on. Runoff during the thawing season caused serious soil erosion but runoff quality during the winter was relatively good. Serious wind erosion from unprotected fields after the fall harvest were obserbed and best management practices to reduce the erosion need to be developed.

• 한국측량학회지
• /
• 제36권5호
• /
• pp.423-432
• /
• 2018

Surface water mapping has been widely used in various remote sensing applications. Water indices have been commonly used to distinguish water bodies from land; however, determining the optimal threshold and discriminating water bodies from similar objects such as shadows and snow is difficult. Deep learning algorithms have greatly advanced image segmentation and classification. In particular, FCN (Fully Convolutional Network) is state-of-the-art in per-pixel image segmentation and are used in most benchmarks such as PASCAL VOC2012 and Microsoft COCO (Common Objects in Context). However, these data sets are designed for daily scenarios and a few studies have conducted on applications of FCN using large scale remotely sensed data set. This paper aims to fine-tune the pre-trained FCN network using the CRMS (Coastwide Reference Monitoring System) data set for surface water mapping. The CRMS provides color infrared aerial photos and ground truth maps for the monitoring and restoration of wetlands in Louisiana, USA. To effectively learn the characteristics of surface water, we used pre-trained the DeepWaterMap network, which classifies water, land, snow, ice, clouds, and shadows using Landsat satellite images. Furthermore, the DeepWaterMap network was fine-tuned for the CRMS data set using two classes: water and land. The fine-tuned network finally classifies surface water without any additional learning process. The experimental results show that the proposed method enables high-quality surface mapping from CRMS data set and show the suitability of pre-trained FCN networks using remote sensing data for surface water mapping.

• 한국물환경학회지
• /
• 제21권5호
• /
• pp.516-519
• /
• 2005

An useful protocol coiled load duration curve methodology to estimate contaminant loading to a river on an exceedance probability scale was developed in this research. The technique was further applied to estimate total coliform loading to the Geum River, using the daily mean flow rate and total coliform concentration data during January, 1996 and July, 2004 for the Gongju where an automated monitoring station is located. Drought flow of the Gongju (=50.3 cms) was equivalent to 40% on an exceedance probability scale. Load duration curve for total coliform loading at the Gongju was constructed. Standard duration curve was constructed with the water quality criteria for the class 2 (total coliform concentration = 1000 MPN/100 mL). By plotting load duration curve with standard duration curve, it could be revealed that water quality do not meet the desired water quality for 47% on an exceedance probability scale. If linearity between flow rate and coliform concentration is assumed, it can be interpretated that water quality exceeds desired criteria when average mean flow rate is over 51 cms.

• 생태와환경
• /
• 제42권4호
• /
• pp.502-509
• /
• 2009

In this study a total of 27 stream sites, at 1 km intervals, were monitored for simple physicochemical water characteristics, land coverage patterns, and stream environment characteristics using the Habitat-riparian Indexing System (HIS), in the Yangsan Stream. The HIS has been tested in previous research, resulting in some identification of advantages in the application to the stream ecosystems data. Even though reliable stream environment characterization was possible using HIS, there was no information about the application of this tool to present continuity of environmental changes in stream systems. Also the necessity was raised to compare the results of HIS application with land coverage information in order to provide useful information in management strategy development. The monitoring results of this study showed that changes of environmental degradation were well represented by HIS. Especially, stream environment degradation due to construction was relatively well reflected in the HIS monitoring results, and the main causality of Yangsan Stream degradation was expansion of the urbanized area. In addition, there were significant relationships between the HIS scores and land coverage information. Therefore, it is necessary to prepare appropriate options in controlling or managing the expansion of the industrialized areas in this stream basin in order to improve the stream environment. For this purpose, ensemble utilization of HIS results, water quality, and geographical information, resulting in integration with remote sensing processes can be possible.

• 한국물환경학회지
• /
• 제32권6호
• /
• pp.511-519
• /
• 2016

National Institute of Environmental Research (NIER) has developed the Korean Reach File (KRF) for scientific and systematic analysis of variables related to water quality, pollutant sources and aquatic ecosystems in consideration of steam reach networks. The KRF provides a new framework for data production, storage, management and analysis for water related variables in relation to spatial characteristics, connections, and topologies of stream reaches. However, the current version of KRF (ver.2) has limited applicability because its nodes include not only the stream points based on topological characteristics but also those based on water quality monitoring stations, which may undermine its generality. In this study, a new version of KRF (ver.3) was designed and established to overcome the weak point of version 2. The version 3 is a generalization of the old KRF graphic data and it integrates the attribute data while separating it from the graphic data to minimize additional work that is needed for data association and search. We tested the KRF (ver.3) on actual cases and convenience and adaptability for each application was verified. Further research should focus on developing a database link model and real-world applications that are targeted to process event data.

• 한국환경보건학회지
• /
• 제47권1호
• /
• pp.45-54
• /
• 2021

Objectives: This study evaluated the odor around an industrial complex area (#1-#5) and the operational effects of the Odor Monitoring System in Seo-gu in Daegu City. Methods: Samples were collected from November 2012 to December 2018 and were analyzed for complex odor. The odor occurrence rate and the odor reduction rate were calculated. Results: In 2018, the mean concentration of complex odor decreased 20.9% and the odor occurrence rate decreased from 65.0 to 27.5% around the industrial complex area (#1-#5) in Seo-gu compared to 2013. After the operation of the Odor Monitoring System, the standard excess rate (3.0%→40.8%) and the excess concentration of complex odor (1,442→4,304) increased at odor-emitting workplaces. In addition, the mean concentration of complex odor (15.9%) and the odor occurrence rate (60.6%→32.9%) around the industrial complex area (#1-#5) and the number of odor complaints (23.4%) in Seo-gu decreased. Conclusion: In order to reduce the odor around the industrial complex area, it is important to improve the odor emitting facilities. The Odor Monitoring System uses scientific and systematic monitoring methods that can help control and manage the odor emission facilities.

• 한국물환경학회지
• /
• 제38권6호
• /
• pp.275-281
• /
• 2022

To maintain water quality after water treatment, monitoring whether the quality of treated tap water quality changes is essential. However, current investigations are insufficient to prevent secondary contamination in drinking water supply systems. This study investigated Gyeonggi's e apartment where a red water problem occurred and monitored the water quality and corrosiveness of the overall water supply system to the apartment from June 2021 to April 2022. In a comparison of drinking water quality after water treatment and the influent of the reservoir, turbidity and heavy metal concentrations were increased and residual chlorine was decreased due to increases in temperature. Correlation analysis and principal component analysis (PCA) indicated that a low level of residual chlorine may cause the abscission of Mn²⁺ and Fe²⁺ through microorganism activation, which also causes a high level of turbidity. The corrosion index (LI) in the influent of the reservoir tank was increased due to Ca²⁺ and temperature. These results indicate that the corrosiveness of drinking water and the deterioration of drinking water quality were mainly increased between the drinking water treatment plant and the reservoir tank's influent. The findings provide clear evidence that it is essential to manage water supply systems and reservoir tanks to prevent the secondary contamination of drinking water.