• Title/Summary/Keyword: Sediment

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A Study on the Prediction of Sediment Yield and its Elevation in Fresh Desalted Reservoirs (담수호의 침전량과 분포 예측에 관한 연구)

  • 김태철;이재용;윤오섭;박승기
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.38 no.2
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    • pp.97-107
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    • 1996
  • This study was performed to derive the formula of sediment yield and predict the sediment elevation for fresh desalted reservoirs. Data analyzed was from 3 fresh desalted reservoirs of Sapkyo, Asan, and Namyang. Average sediment yield calculated from the sediment survey data was $279m^3/km^2/$ year for Sapkyo lake, $523m^3/km^2/$ year for Namyang lake, and $190m^3/km^2/$ year for Asan lake. The trap efficiency for Sapkyo lake was 63%. The formula of sediment yield was derived as $Q_s=6,461{\times}A{^-0.44}$ for fresh desalted reservoir. Sediment yield in fresh desalted reservoirs was much higher than that in inland reservoirs located in the same watershed, because of long trap time in fresh desalted reservoirs.

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The Points of Issue and Countermeasure for Sediment Control Dam Designs (사방댐 설계방법의 문제점과 그 대책)

  • Kim, Woon-Hyung;Song, Byung-Woong;Kim, Burm-Suck;Kim, Ju-Han;Lee, Kyung-Hee
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.09a
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    • pp.1057-1064
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    • 2009
  • Since the global warming causes debris flow damage has increased in Kangwon Area, Sediment control dam have increasingly founded to protect the damage. In spite of the realities design methods are well not established to determine type of the dam, design parameters and maintenance. Through comparison for design methods to sediment control dam in Korea, it raised some points to improve to correspond with realities. In addition, it pointed that some issues for the sediment control dams in Kangwon Area. Those are shown that unclear positions of the dams, unremoval of sediment, occurrence of seepage under the dams and uninstallation of roads to remove sediment. In addition, the countermeasure for the issues are proposed.

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Elution Behavior of Nutrient Salts from Sediment and its Impact on Water Bodies

  • Wada, Keiko;Haruki, Fumio;Ishita, Kyoji;Okada, Yuki
    • Environmental Engineering Research
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    • v.15 no.1
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    • pp.41-48
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    • 2010
  • This paper describes the influence of nutrient salts eluted from the bottom of a closed water area where polluted sediment has been deposited by inflowing river water. The elution pattern was monitored at our experimental facility. Both the sediment pore water and water above the bottom were sampled using a dialyzer sampler (peeper). The pore water of the eutrophicated sediment contained a large amount of nutrient salts, and the effect of elution was confined to a limited area of the bottom surface. The nutrient concentration of the sediment pore water was closely related to both the water temperature and dissolved oxygen (DO) concentration. The eluted nutrients from the sediment provided a source for phytoplankton and algae growth. This experimental data indicated that the water quality of the surface was not directly connected to the eluted nutrient salts, while it was indirectly affected by the total ecosystem, including all the organisms within an area and their environment.

Sediment Preference and Burrow Shape of Spoon Worm, Urechis unicinctus (Von Drashe) in Laboratory Culture (실험실 사육에 의한 개불, Urechis unicinctus의 저질선택성과 굴의 형태)

  • 강경호
    • Journal of Aquaculture
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    • v.12 no.3
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    • pp.193-196
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    • 1999
  • In order to obtain the basic data for the effective seed production of Ureshis unicinctus sediment preference, burrow shape and burrowing depth in sediment were investigated in the laboratory. The highest valus in both sediment preference and burrowing rate of U. unicinctus were shown at fine and (0.11~0.50mm in the mean diameter). U. unicinctus made various types of burrows, such as J, L, S and U shapes. Generally only one individual inhabits in burrow with head-up.

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Dynamics of Sand Ripples Generated by Irregular Waves

  • Kim, Kyuhan-
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 1993.07a
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    • pp.98-100
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    • 1993
  • When we want to reproduce transport of sediment in the fields in a laboratory, we have to establish a similitude law. A similitude law is necessary when sediment transport of field is reproduced in a laboratory. When we apply our knowledge about sediment transport obtained in the laboratory to predict sediment transport in the field, we can apply Froudian law to a fluid motion that becomes agitation agency and transporting flow of sediment movement. (omitted)

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Physicochemical Properties of Yanggaeng with Lentil Bean Sediment (렌틸콩 앙금 첨가에 따른 양갱의 품질 특성)

  • Noh, Dan-Bi;Kim, Kyoung-Hee;Yook, Hong-Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.6
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    • pp.865-871
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    • 2016
  • This study investigated the quality characteristics of Yanggaeng added with lentil bean sediment. Yanggaeng was prepared by addition of 0, 25, 50, and 75% (w/w) lentil bean sediment to white bean basic formulation. For the proximate composition measurement, lentil bean sediment consisted of 15.63% moisture, 17.31% crude protein, 0.92% crude ash, and 0.31% crude fat. The sediment yield of lentil beans was 54.25%. The moisture content of Yanggaeng significantly increased with increasing lentil bean sediment content. The total soluble solid content ($^{\circ}Brix$) of Yanggaeng significantly decreased with increasing lentil bean sediment content, whereas the pH was not significantly different between the control and experimental groups. The lightness of Yanggaeng significantly decreased with increasing lentil bean sediment content, whereas redness and yellowness significantly increased with increasing lentil bean sediment content. The springiness, gumminess, and chewiness of Yanggaeng decreased with increasing lentil bean sediment content, whereas hardness and cohesiveness was not significantly different between the control and experimental groups. The total phenolic content and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity significantly increased with increasing lentil bean sediment content. Yanggaeng containing 25% lentil bean sediment had acceptable sensory properties, such as taste, texture, and overall preferences. Thus, our results suggest that Yanggaeng containing 25% lentil bean sediment could improve the sensory properties and antioxidant activities of Yanggaeng.

An Experimental Study on the Pond Sediment and Water Quality Purification using Oxygen Solubilization Device(OSD) System (산소용해수를 이용한 호소 저질 및 수질개선에 관한 실험적 연구)

  • Kim, Young-Taek;Bae, Yoon-Sun;Roh, Eun-Kyung;Park, Chul-Hwi;Lee, Yeon-Ku
    • Journal of Korean Society of Water and Wastewater
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    • v.20 no.1
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    • pp.94-103
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    • 2006
  • The pollution in closing water can be caused by not only artificial factor like sewage but also natural factor like elution from sediment. In this study we analyzed Sediment Oxygen Demand (SOD) for verification of sediment purification effect and sediment elution experiment as well as general items like COD, TN, TP, SS to complement and assess the effect of sediment and water quality. The experiment result showed that the release rate of OSD system were 4 times and 3 times as large as control for P and Fe respectively. SOD for operated OSD system and control were $12.18gO_2{\cdot}m^{-2}{\cdot}d^{-1}$ and $47.95gO_2{\cdot}m^{-2}{\cdot}d^{-1}$. From water qualities analyzed by COD, TN, TP, SS, chlorophyll-a, the removal efficiency increase of TN, TP, chlorophyll-a and COD were about 10~20%, 40~50% and 10% respectively. In conclusion, OSD can contribute to improvement of both the waterbody and the sediment environment effectively.

The Distribution Characteristics of Heavy Metals in the Water, Sediment and Soil along the West Nakdong River (서낙동강 유역의 강물, 저토 및 토양의 중금속 분포 특성)

  • Park, Heung-Jai;Park, Jong-Kil;Park, Won-Su
    • Journal of Environmental Science International
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    • v.3 no.4
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    • pp.409-416
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    • 1994
  • This study was Performed to evaluate the contents of heavy metals in water, sediment and soil of the 7 different sampling points along the West Nakdong river, The results were as follows: the concentrations of Zn, p, Pb, Cd, Mn, Cu and As in the sediment were 197.48, 551.85, 67.01, 2.54, 491.39, 42.95 and 10.52ppm, respectively. The concentrations of Zn, p, Pb, Cd, Mn, Cu and As in the soil was 83.32, 482.89, 17.15, 1.02, 226.02, 26.15 and 7.29ppm, respectively. The concentration ratios of heavy metals In the water to the sediment were 593 - 12700 (Cd >> Cu > Zn > Mn > As > Pb) and that of the water to the soil were 152 - 5100 (Cu > Cd > Zn > Mn > As >Pb). The correlation coefficients of Cu and Pb weve high among the water, sediment and soil. Because the accumulation amounts of heavy metal in the sediment were high, the concentration of heavy metals in the sediment was higher than in soil. The correlation coefficient of heavy metals among water, sediment and soil was high (0.79 - 0.95). Key Words Distribution Characteristics, heavy metals, West Nakdong River.

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Chlorophyll-a and its Degradation Products of the Sediment in the Downstream of the Nakdong River

  • Jung, Ha-Young;Cho, Kyung-Je
    • Korean Journal of Environmental Biology
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    • v.21 no.4
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    • pp.415-421
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    • 2003
  • Chlorophyll-a and its degradation products (pheopigment) contained in the sediment were determined to evaluate the eutrophication status in the downstream of Nakdong River. The chlorophyll-a and pheopigment concentrations of sediment ranged 11-646 mg $\mu \textrm m^{-2}$ (mean 172 mg $\mu \textrm m^{-2}$) and 48-1,564 mg $\mu \textrm m^{-2}$ (mean 454 mg $\mu \textrm m^{-2}$) over 11 sampling stations of the Nakdong River. The chloropigment concentrations in this local area were higher than other values reported previously and this river waters showed hypertrophic status in view of sedimentary chloropigment. Total chloropigment standing crops of sediment, which are the residuals after the longterm degradation, were 2.2-3.6 fold higher than chlorophyll-$\alpha$ contents of overlying water. The amounts of chloropigments of sediment suggest a large contribution of phytoplankton to the sediment. While chloropigment standing crops are evaluated with organic-C and nitrogen contents, the algal contribution to the carbon and nitrogen pool of the sediment were estimated to be approximately 30% and 40%, respectively.

Sediment Transport Prediction Model in a Harbor by Finite Element Method (유한요소법(有限尿素法)에 의한 항만(港灣)에서의 토사이송추정모형(土砂移送推定模型))

  • Yoon, Tae Hoon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.2 no.2
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    • pp.19-28
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    • 1982
  • The development of unsteady, depth-averaged two dimensional sediment transport prediction model in estuaries and harbors by the Galerkin finite element technique is presented. The model consists of two submodels, flow induced circulation model and sediment transport model. The sediment transport submodel is formulated by incorporating sediment continuity equation and sediment diffusion equation. Numerical experiments of the model, which were carried out in one dimensional channel under different conditions for circulation and sediment transport, show the adaptability of the formulation for predicting the migration of both cohesive and noncohesive sediments. The model was applied to Busan harbor to simulate circulation and sediment transport for simplified conditions. Of the results by the model the flow pattern are shown to be similar to observed data.

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