• 한국물환경학회지
• /
• 제30권2호
• /
• pp.119-127
• /
• 2014

The objective of this study is to evaluate and analyze Sumjin River Basin water environment system. It was necessary to improve the water quality. The data were collected from 2010 January to 2012 December including Water Temperature, pH, DO, EC, $BOD_5$, COD, TOC, SS, T-N, T-P. The data were used to study were required to; Correlation Analysis; Principle Component Analysis; Factor Analysis. The results were as followed. According to correlation analysis on $BOD_5$ against COD, TOC it revealed that the each value of correlation coefficient were 0.715 and 0.719; this means the strength of the relationship is strong. The same analysis on T-P against $BOD_5$, COD, TOC, SS has revealed that the range of the correlation coefficient value fell between 0.482 and 0.608 which means strength of the relationship between them remained normal. Through correlation analysis, it has been found that all elements except T-N have high correlation. The results of principal component analysis to target the overall water quality was extracted to three main components. The cumulative contribution rate is 68.990%. In the case of seasonal water quality, Spring and Summer are extracted to each of four main components. The cumulative contribution rate is 81.515% and 73.550% respectively. Fall and Winter are extracted to each of three main components. The cumulative contribution rate is 65.072% and 72.721% respectively. There is no seasonality in the case of factor analysis. The first common factor is $BOD_5$, COD, TOC, SS, T-P, which were classified. Totally speaking, Sumjin River Basin water system gets highly affected by the nutrient salts, organic matter and suspended solid at the same time.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
• /
• pp.833-836
• /
• 2008

본 연구는 기존 벤토나이트 방수재가 염수환경의 지하구조물 적용에 있어서 초기 수화에 의한 팽창이 안 됨으로써 염수의 침입을 허용하여 구조물이 누수로 이어지는 문제점을 보완하기 위하여 최근 개발된 사전수화 시킨 형태의 벤토나이트 쉬트에 관하여 염수환경 적용 특성을 중심으로 연구하고자 하였다. 이를 위해 본 연구에서는 사전수화형 벤토나이트 시트를 대상으로 염수환경을 기본 전제조건으로 한 상태에서 점결성, 팽윤성, 투수성 등의 시험을 통하여 그 성능특성의 변화를 중점 고찰하였다. 본 연구결과 염수환경에서 초기 투수를 허용하지 않았으며, 최대 $3kgf/cm^2$ 수압으로 72시간까지 투수가 발생하지 않았다. 점결성과 팽윤성 확인결과 담수환경에서는 겔화의 충분한 진행이 확인 되었고, 염수환경에서는 판상구조의 갈라짐 현상이 보였으나 이는 벤토나이트가 수화하면서 결정층간이 팽윤된 것으로 판단된다. 따라서 방수재 상부에 누름층과 같은 압밀조건이 형성된다면 염수환경의 지하구 조물 적용에 있어서 기대가된다.

• 한국물환경학회지
• /
• 제26권5호
• /
• pp.834-840
• /
• 2010

To find out the toxin production characteristics of Korean harmful cyanobacteria, we isolated 14 cyanobacterial strains from Korean lakes and rivers and analyzed the kinds and cellular content of microcystins (MCYSTs) of cyanobacterial isolates using cultured biomass. And we measured the MCYSTs production by growth phase of two representative toxic strains, Microcystis aeruginosa (HG-015) and Anabaena planktonica (HG-012). Among seven cyanobacteral species, Microcystis wesenbergii showed the highest cellular MCYSTs content. MCYST-RR was the most dominant toxin reaching more than 85% of MCYSTs produced by isolated cyanbacterial strains. During the mass culture, Microcystis aeruginosa (HG-015) showed the highest yield and accumulation of MCYSTs in the exponential growth phase. However the cellular content of chlorophyll a and MCYSTs of Anabaena planktonica (HG-012) showed higher value in the stationary and early death phase than in the exponential growth phase. Our results suggest that control and removal of harmful cyanobacterial bloom before exponential growth phase may be effective to prevent health risk of cyanobacterial toxins in the drinking water sources.

• 한국해양공학회지
• /
• 제28권1호
• /
• pp.64-68
• /
• 2014

This study was conducted to investigate the durability of carbon fiber/epoxy composites (CFRP) in a saline water environment. The carbon fiber/epoxy composites were modified to use nanoparticles such as carbon nanotubes and titanum oxide. These hybrid composites were exposed to a saline water environment for a certain period. The weight gain according to the immersion time, a quasi-static tensile test, and micro-graphic characterization were used to investigate the samples exposed to the saline water environment. The weight gains increased with increasing immersion time. The weight gains of the hybrid composites were lower than that for pure CFRP throughout the entire immersion time. The tensile strengths decreased with increasing immersion time. The tensile strengths of the hybrid composites were higher than that of the pure CFRP throughout the entire immersion time. The pure CFRP was observed to be more degraded than the hybrid composites in the saline water environment. Therefore, it was concluded that the addition of nanoparticles to CFRP could lead to improved durability in a saline water environment.

• 한국환경농학회지
• /
• 제31권2호
• /
• pp.200-204
• /
• 2012

BACKGROUND: Recently, the project for improvement of water quality and preservation of the Yeongsan and Seomjin river basin was actively promoted. However, the publicity for many results of the project is not actively done, thus they are rarely used. Furthermore, there are not sufficient information about the projects preformed by other research institutions. Therefore, the watershed management system for efficient water management is needed in the Yeongsan and Seomjin river basin. CONCLUSION: Firstly, establishment of the Yeongsan and Seomjin river basin management research center, Secondly, construciton of wed-based water management research network. These results will serve as a basic data for efficient water management.

• Water Engineering Research
• /
• 제6권2호
• /
• pp.63-71
• /
• 2005

Nowadays Climate disasters are frequently happening due to occasional occurrences of EI Nino and La Nina events and among them, water shortage is one of the serious problems. To cope with this problem, climate model simulations can give very helpful information. To utilize the climate model for enhancing the water resources planning techniques, probabilistic measures of the effectiveness of global climate model (GCM) simulations of an indicator variable for discriminating high versus low regional observations of a target variable are proposed in this study. The objective of this study is to present the various analysis methods to find the suitable application methods of GCM information for Korean water resources planning. The basic formulation uses the significance probability of the Kolmogorov-Smirnov test for detecting differences between two variables. The various methods for adopting correct association, changing the window size, discrimination condition, and the use of temporally down scaled data were proposed to find out the suitable way for Korean water resources planning.

• 한국물환경학회지
• /
• 제28권3호
• /
• pp.359-366
• /
• 2012

Accurate predictions about the water quality of a river have great importance in identifying in-stream flow and water supply requirements and solving relevant environmental problems. In this study, the effect of water release from upstream dam on the downstream water quality has been investigated by applying a hydological model combined with QUAL2E to Geum River basin. The ESP (Ensemble Stream Prediction) method, which has been validated and verified by lots of researchers, was used to predict reservoir and tributary inflow. The input parameters for a combined model to predict both hydrological characteristics and water quality were identified and optimized. In order to verify the model performance, the simulated result at Gongju station, located at the downstream from Daecheong Dam, has been compared with measured data in 2008. As a result, it was found that the proposed model simulates well the values of BOD, T-N, and T-P with an acceptable reliability.

• 한국암석학회:학술대회논문집
• /
• 한국암석학회.한국광물학회 2000년도 공동학술발표회 논문집
• /
• pp.3-11
• /
• 2000

The earth environment consists of four spheres : geosphere, hydrosphere, atmosphere and biosphere. The geosphere consists mostly of minerals. It, however, contains some water and air in its shallow depth. Although hydrosphere and atmosphere consist predominantly of water and air, respectively, both contain some minerals. The biosphere consisting of various organisms is present in the interfaces of geosphere, hydrosphere and atmosphere. The natural environment of the earth is continuously changing by the interaction of four spheres. It suggests that out relevant environmental problems can not be revolved without understanding the natural relationship of these four spheres. Minerals in our environment are very important because they are the main constituent materials of the earth and they control our environment. The roles of minerals in our environment have not been understood even in the scientific society. Thus their roles have been neglected. Review of studies on the environmental mineralogy so far made at our laboratory and others show that minerals control the environment in various ways. Minerals neutralize the acid water as well as acid rain. Minerals in soils and rocks are major neutralizer of the acid rain. Salinization of sea water is attributed to the ionic substitution between minerals and sea water. Some minerals control the humidity of the air. Corals, the products of biomineralization, are the main carbon controller of the air. Minerals also adsorb heavy metals, organic pollutants and radioactive nuclides. Such remarkable functions for controlling the environment come from the mineral-water reaction and biomineralization. All these phenomena are subjects of the environmental mineralogy, a new field of earth science.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2005년도 학술발표회(1)
• /
• pp.255-256
• /
• 2005

• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2008년도 하계학술발표대회 논문집
• /
• pp.493-498
• /
• 2008

The several water resources are showed recently the various pollution types due to the industrialization and the disarranged district development. The living waste water, plant waste water and so are contaminated continuously and the recycling water is concerned highly to save the cost and to improve the environment as the general people. The dust and the heavy metal in the air and the acid rain are contaminating the river water and the underground water. The clean environment is on the rise to the general people and is to be the social problems. There is going to complement and repair the water supplying and fire extinguishing pipeline to save the construction cost and improve the environment in the construction facilities parts. Therefore, in this paper the recycling water treatment/supply apparatus using the living waste water is considerated technically and is raised on the practical uses.