• Title/Summary/Keyword: Water impact

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Analysis of Flood Level Variation in Oship Stream Using HEC-RAS: Focuses on the Impact of the Typhoon Sanba (HEC-RAS를 이용한 오십천의 수위변화 해석: 태풍산바의 영향을 중심으로)

  • Jun, Kye-Won
    • The Journal of the Korea Contents Association
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    • v.13 no.2
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    • pp.498-504
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    • 2013
  • Recently, the frequency of typhoons have increased due to the effects of climate change. As a result, in mountain streams, it has caused streamflow increase upstream and frequent water surface elevation downstream. This study analyzed the effects of the heavy rainfalls caused by Typhoon Sanba, which had a direct impact on Korea between September 17 and 18, on the water level variations downstream in mountainous streams. In addition, the drainage basin of Samcheok Oship stream was chosen as the object of this study. This study analyzed the flood level by applying HEC-RAS model. The observed water level measured in 2012 and the water level simulated by HEC-RAS model showed similar results. In addition, the simulation results showed the maximum flood level was 5.32m the mean flow velocity was 2.33m/sec and the maximum channel water depth was 7.51m. The analysis showed that the heavy rainfalls caused by Typhoon Sanba had an impact on the water surface elevation in Oship stream. The final results from this study will give a reasonable and important data to perform the Design of Hydraulic Structure.

Water Quality Modeling of Daechong Reservoir by WASP5/EUTR05 Model (WASP5에 의한 대청호 수질모델링)

  • Lee, Jong Ho
    • Journal of Environmental Impact Assessment
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    • v.8 no.1
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    • pp.93-105
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    • 1999
  • Lately water quality of Daechong Reservoir has become more eutrophicated than ever before and there has been much concern over especially the eutrophication of the embayment near Daejon and Chongju Water Intake Tower every summer. The purpose of this study is to predict the impact of change in the pollutant loading, flowrate, nitrogen and phosphorus release from sediment, SOD(sediment oxygen demand) upon the water quality of Daechong Reservoir by WASP5/EUTR05 in order to suggest water quality management alternatives. The data of Sep. 1995 were used for the calibration of the model and those of Sep. 1997 was for verification. The result of the modeling can be summarized as follows. 1. The 50% increase(decrease) of pollutant loading has caused that of T-N concentration by 0.10-0.14 mg/l, T-P concentration by 0.003-0.005 mg/l, and CBOD concentration by 0.16-0.18 mg/l. But the ratio of DO change by the change of pollutant loading was relatively small. 2. The sensitivity test of NH4 flux to T-N and that of P04 flux to T-P shows that T-N and T-P concentration were changed more in the epilimnion segments (SEG4, SEG5, SEG6, SEG7) than the other segments. As SOD increases, DO was predicted to decrease more especially in the hypolimnion (SEG9-SEG14). 3. As flowrate increase, the concentration of T-N, T-P, and CBOD were predicted to decrease, but DO concentration increased especially in the hypolimnion segments(SEG11, SEG12, SEG13, and SEG14). As the flowrate changed from $119m^3/sec$ to $50m^3/sec$, the concentration of T-N and CBOD in the hypolimnion was predicted to decrease.

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Water-soluble ginseng oligosaccharides protect against scopolamine-induced cognitive impairment by functioning as an antineuroinflammatory agent

  • Xu, Ting;Shen, Xiangfeng;Yu, Huali;Sun, Lili;Lin, Weihong;Zhang, Chunxiao
    • Journal of Ginseng Research
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    • v.40 no.3
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    • pp.211-219
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    • 2016
  • Background: Panax ginseng root is used in traditional oriental medicine for human health. Its main active components such as saponins and polysaccharides have been widely evaluated for treating diseases, but secondary active components such as oligosaccharides have been rarely studied. This study aimed to assess the impact of water-soluble ginseng oligosaccharides (WGOS), which were isolated from the warm-water extract of Panax ginseng root, on scopolamine-induced cognitive impairment in mice and its antineuroinflammatory mechanisms. Methods: We investigated the impact of WGOS on scopolamine-induced cognitive impairment in mice by using Morris water maze and novel object recognition task. We also analyzed the impact of WGOS on scopolamine-induced inflammatory response (e.g., the hyperexpression of proinflammatory cytokines IL-$1{\beta}$ and IL-6 and astrocyte activation) by quantitative real-time polymerase chain reaction and glial fibrillary acid protein (GFAP) immunohistochemical staining. Results: WGOS pretreatment protected against scopolamine-induced learning and memory deficits in the Morris water maze and in the novel object recognition task. Furthermore, WGOS pretreatment downregulated scopolamine-induced hyperexpression of proinflammatory cytokines interleukin (IL)-$1{\beta}$ and IL-6 mRNA and astrocyte activation in the hippocampus. These results indicate that WGOS can protect against scopolamine-induced alterations in learning and memory and inflammatory response. Conclusion: Our data suggest that WGOS may be beneficial as a medicine or functional food supplement to treat disorders with cognitive deficits and increased inflammation.

Analysis of Effectiveness for Water Cycle and Cost-Benefit according to LID Application Method in Environmentally-Friendly Village (친환경시범마을의 LID 적용에 따른 물순환 효과 및 비용편익 분석)

  • Baek, Jongseok;Lee, Sangjin;Shin, Hyunsuk;Kim, Hyungsan
    • Journal of Korean Society on Water Environment
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    • v.34 no.1
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    • pp.57-66
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    • 2018
  • Water disasters such as flash floods and inundation caused by localized heavy rainfall in urban areas have a large impact on climate change but are also closely related to the increase in impervious areas as pointed out in domestic and international studies. It is difficult to secure natural green areas in urban areas that have already been developed. So, urban regeneration can be expected using water management optimized with technologies to secure infiltration and storage capacity such as Low-Impact Development technology. In this study, the water cycle improvement ability was confirmed by applying the LID technology within the district unit plan of the environmentally friendly village, and the economic feasibility of LID application was analyzed by estimating the costs and benefits of installing the facilities. The site was planned to conserve sufficient green and plans for securing the watershed infiltration and storage capacity were formulated with the application of additional LID technology, such as infiltration trenches, rain barrels and permeable pavements. The LID design method applicable to the site was established, and the water balance of the watershed was analyzed through simulations of the SWMM model. The water circulation improvement effect was confirmed through the water balance analysis, and the cost-benefits were determined according to the estimation method, and the economic analysis was conducted. This study confirms that the investment of LID technology is economically feasible for the hydrological improvement effect of the housing complex.

Environmental Management towards Sustainable Urban Development of Chongju City (지속가능한 도시개발을 위한 환경관리방안의 모색 - 청주시를 중심으로 -)

  • Lee, Jong-Ho
    • Journal of Environmental Impact Assessment
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    • v.4 no.2
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    • pp.131-149
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    • 1995
  • The object of this study is to suggest some alternatives for environmental management towards sustainable urban development of Chongju city in Korea. This study analyses urban environmental indicators (population density, land use, road, park, car, etc.), level of air and water pollution and solids waste generation by comparing Chongju city and other large cities. Some alternatives towards sustainable development in Chongju city would be summerized and suggested as higher concentrated land use(compact city), mixed land use, supply of mass transit, establishment of regional environmental standards, total emission regulation of air and water pollutants, the preparation of Local Agenda21 of Chongju, and the introduction of strategic environmental assessment(SEA) into environmental impact assessment.

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A study on the improvement for performance of floor finishing materials using poly urethane with water reacting urethane (수반응 우레탄과 바닥용 경질 폴리우레탄을 이용한 바닥마감재의 성능향상에 관한 실험적 연구)

  • Kang, Hyo-Jin;Park, Jin-Sang;Park, Jong-Ook;Oh, Sang-Keun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.05b
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    • pp.653-656
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    • 2006
  • It is necessary for the new material and construction concept to make up for weak point which related to high durability and finish ability to solve exposure limit of exist construction method. This paper is deal with performance test(tier load, anti abrasion, anti impact, permeability, bond test) compositive using for water reacting soft urethane and rigid urethane to improve the exist problem which are crack movement, adhesive on the wet surface, impact and abrasion by tier load. It is getting decreasing demage compare with other exist materials after test by transfer load, movement and impact.

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Root-Cause Investigation of Abnormal Sound from a Heat Exchanger of Condensate Water System in a Nuclear Power Plant (원전 복수계통 열교환기의 이음발생 원인규명)

  • Lee, Jun-Shin;Kim, Tae-Ryong;Lee, Wook-Ryun;Sohn, Seok-Man;Yoon, Seok-Bon;Kim, Man-Hee
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.05a
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    • pp.1306-1311
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    • 2006
  • The root cause of abnormal sound from a heat exchanger of condensate water system in a nuclear power plant is investigated by using the impact signal-processing methodology based on the Hertz theory. The predicted results for the location of impact force and the loose part size meet good agreement with the identified materials during the overhaul period in the plant. Nuclear power plants have experienced several loose parts and the frequency of the loose part will be increased along the aging of the plants. So, this analysis methodology for the impact signal will be widely utilized for the primary and secondary side of the nuclear power plant.

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Assesment of Water Quality Standards using Stochastic Distribution Characteristics between Dynamic Modeling Results and Observed Data (동적수질예측결과의 확률분포특성을 이용한 목표수질 달성가능성 평가)

  • Ha, Sung-Ryong;Lee, Ji-Heon;Seo, Se-Deok;Lee, Seung-Chul;Park, Jung-Ha
    • Journal of Environmental Impact Assessment
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    • v.17 no.1
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    • pp.47-56
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    • 2008
  • Total Maximum Daily Load(TMDL) is a core basin management system to assign total emissions of pollutants to unit basin and emission source within a limit of the target water quality and to secure sustainability. considering "Environment and development" together. By current technical guidance of TMDL, the water quality in the riverbed of which the target water quality is noticed, must achieve the target; and the water quality standard for evaluating achievement of the target should be prescribed as non-excessive probability quality of water on the basis of the pertinent water quality documents. Therefore, the study calculated the target water quality by each unit basin which the target water quality must be noticed through the analysis of probability for water quality documents in rivers at the time of establishing a plan, and the study evaluated the achievement possibility of the target water quality by analyzing and comparing the target water quality plan with the standard water quality to evaluate the achievement of the target water quality. As the result, applying the proposed method to Mihocheon River system, it is concluded that selected the target water quality (Each BOD 3.3mg/1 and BOD 3.0mg/1) in Miho A and Musim A is available. Of course, it showed that the target water quality: BOD 2.5mg/1 in Miho A and BOD 3.0mg/1 in Musim A, could be achieved if the small reduction in B unit area was implemented.

Review on Water Quality and Achievement of Water Quality Goal by Various Evaluation Methods in Geum River (다양한 평가기법을 이용한 금강 대권역의 수질 및 목표수질기준 달성도 평가)

  • Lee, Jae-Woon;Jeong, Hye-Sung;Yoon, Jung-Hee;Cheon, Se-Uk
    • Journal of Environmental Impact Assessment
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    • v.17 no.6
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    • pp.373-380
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    • 2008
  • The Ministry of Environment plans to improve quality of water which is achieved over 85% in rivers and 94% in lakes of the whole country as "Good Water" until 2015. Also, the law of evaluation of water quality and water quality goal were made newly. So, the water quality has evaluated by using new law since 2007. This study evaluated whether "Good Water" and" Water Quality Goal" were achieved or not in 22 middle-sized districts and major 10 lakes of Geum river. The achievement rates of rivers decreased and the achievement rates of lakes mostly were the same for 5 years. In 2007, the achievement rates of "Good Water" were 50% in rivers and 50% in lakes. The achievement rate of "Water Quality Goal" were 59.1% in rivers and 20% in lakes. The water quality in 2007 was evaluated worse than last year in case of rivers. The evaluations of Korea-Comprehensive Water Quality Index(K-CWQI) showed that achievement rates of "Water Quality Goal" were 81.8% in rivers and 0% in lakes. The statistical correlation analysis showed that correlations between BOD and COD were meaningful at the downstream, compared to upstream, generally. In case of lakes, correlations between COD and temperature were meaningful. Also, correlations between COD and Chl-a were meaningful. The Trophic State Index ($TSI_{KO}$) showed that the half of lakes are major over eutrophic status in lakes. These analytical methods such as K-CWQI, $TSI_{KO}$, statistical correlation analysis could be additionally helpful for evaluation of water quality and provide basis data for understanding characteristics of watershed in Geum river.

Distribution of the Organic Contents in Reservoir Sediment (호소 퇴적물의 유기물 분포)

  • Hwang, Jong Yeon;Han, Eui Jung;Yu, Soon Ju;Yoon, Young Sam;Cheon, Se Eug;Kim, Tae Keun
    • Journal of Environmental Impact Assessment
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    • v.8 no.2
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    • pp.95-107
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    • 1999
  • The organic contents of reservoir sediment can offer a good indicator to events in history of lake life. Reservoir sediment have many information of the past and future fingerprint about development direction of life cycle in biological animals. So, in this study we made an effort to know the distribution of organic contents in Daecheong reservoir sediment. Items for this investigations are such as follows: Loss on ignition, COD, Organic carbon, TN, TP, heavy metal contents, Loss on ignitions were determined in 6.44~15.91% and COD were determined in 1.606~6.859%, organic carbon in 1,077~3.743%. Contents of TP and TN were in the range of 0.083~0.757%, and 0.645~0.926%, respectively.

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