• Title/Summary/Keyword: Mud System

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Ecological Toxicity Assessment in Wetland Sediments (습지 퇴적물의 생태 환경독성도 평가)

  • Lee, Chan-Won;Kwon, Young-Taek
    • Journal of Wetlands Research
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    • v.2 no.1
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    • pp.69-85
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    • 2000
  • Wetlands are generally thought to be among the most fertile and productive ecosystems of the world. They provide a variety of ecological functions to the landscape. In recent years there has been considerable research activity to generate more scientific documentation on the ecological functions of wetlands. Many pollutants released to the environment settle and accumulate in the silt and mud called sediment on the bottoms of wetlands. Contaminated sediment can cause adverse effects to aquatic organism and eventually to ecological system. Sediment toxicity test with water fleas has been done by standardized preparation method of pore and elutriate water methods described in the literature for the need to protect Woopo wetlands. The results of Daphnia magna, Ceridaphnia dubla and Simocephalus sp. toxicity test were compared and discussed in terms of the relative sensitivity and discrimination abilities with both pore and elutriate water obtained from the sediments of Woopo wetlands.

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Cooperative Opportunistic Beamforming for OCI Mitigation in Correlated Multi-User MISO Cellular System (채널 상관도가 존재하는 다중 사용자 MISO 환경에서 인접 셀 간섭 제거를 위한 협력 기회적 빔포밍 기법)

  • Cho, Hee-Nam;Lee, Jin-Woo;Lee, Yong-Hwan
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.289-290
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    • 2008
  • We consider cooperative opportunistic beamforming that can mitigate the other cell interference (OCI) in correlated multi-user multiple-input single-output (MISO) cellular environments. By only exploiting the spatial channel information of adjacent cells, the proposed scheme generates the cooperative random beam that statistically avoids the OCI from adjacent cells. Each cell selects a user in an opportunistic manner. Thus, the proposed scheme can simultaneously achieve the multi-user diversity (MUD) gain and the OCI avoidance gain.

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Development of Single-tube Multiplex Immunocapture RT-PCR Assay for Simultaneous Detection of Two Pepper Tobamoviruses

  • Kim, Jae-Hyun;Choi, Gug-Seoun;Kim, Jeong-Soo;Lee, Sin-Ho;Choi, Jang-Kyung;Ryu, Ki-Ryun
    • The Plant Pathology Journal
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    • v.22 no.2
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    • pp.164-167
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    • 2006
  • An immunocapture reverse transcription-polymerase chain reaction (IC/RT-PCR) was developed for simultaneous detection of two pepper-infecting RNA viruses, Pepper mud mottle virus (PMMoV) and Tobacco mild green mosaic virus (TMGMV). The assay could be performed in a single tube for simultaneous and sensitive detection of these tobamoviruses. This detection system revealed thousand-fold increase in detection sensitivity compare to ELISA. This method could save time and reagent cost compare to common RT-PCR which needs several reactions and several procedures of viral RNA extractions for the same number of samples.

Dry Shrinkage Characteristic according to the Ternary System Inorganic Binder Panel Size (3성분계 무기결합재 패널크기에 따른 건조수축 특성)

  • Lee, Jin-Woo;Lee, Sang-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.11a
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    • pp.144-145
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    • 2014
  • In the cement,that is the main materials of the panel, as to the cofired process, more than 1,300 enormous energies is consumed, in addition the greenhouse gas generated in the process of producing the cement occupies 6.3% of the country whole emission quantity. And the carbon dioxide of about 0.8 ton is the cement ejected in 1 production. Accordingly, the panel utilizing the industrial byproduct is developed. Accordingly, this research is the experiment which makes the individual size into the environment-friendly inorganic binder panel and by using the blast furnace slag, which is the industrial byproduct with the cement substitute material red mud, silica fume, and etc. looks at the dry shrinkage. The length variation in which the panel which is 450 with the dry shrinkage result of measurement, thickness 12mm, and size 450mm is the smallest was shown.

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Turbulence of the Coastal Atmospheric Surface Layer and Structure of the Coastal Atmospheric Boundary Layer (해안 대기 표층의 난류와 해안 대기 경계층의 구조)

  • Kwon, Byung-Hyuk
    • Journal of Fisheries and Marine Sciences Education
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    • v.17 no.3
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    • pp.404-412
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    • 2005
  • The surface energy budget depends on many factors, such as the type of surface, the soil moisture and the vegetation canopy, the geographical location, daily, monthly and seasonal variations, and weather conditions. In the coastal region, the surface is not homogeneous at various scales for instance water, sand, mud, tall grass, and crops. The energy balance over the vegetation canopy was analyzed with the optical energy balance measuring system. The latent heat flux was more intensive than the sensible heat flux. The sensible heat flux was very small in summer due to the canopy effect and higher in spring and autumn. In summer the development of the atmospheric boundary depended on rather the vertical shear of wind than the sensible heat flux.

Variations in Air Temperature and Water Temperature with Tide at the Intertidal Zone : Odo Island, Yeosu (조간대에서 조위에 따른 기온과 수온 변화 : 여수 오도섬)

  • Won Gi Jo;Dong-hwan Kang;Byung-Woo Kim
    • Journal of Environmental Science International
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    • v.31 no.12
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    • pp.1027-1038
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    • 2022
  • The intertidal zone has both land and marine characteristics and shows complex weather environments. These characteristics are suited for studying climate change, energy balance and ecosystems, and may play an important role in coastal and marine weather prediction and analysis. This study was conducted at Odo Island, approximately 300m from the mainland in Yeosu. We built a weather observation system capable of real-time monitoring on the mud flat in the intertidal zone and measured actual weather and marine data. Weather observation was conducted from April to June 2022. The results showed changes in air temperature and water temperature with changes in the tide level during spring. Correlation analysis revealed characteristic changes in air temperature and water temperature during the day and night, and with inundation and exposure.

Long-term Changes of Bathymetry and Surface Sediments in the dammed Yeongsan River Estuary, Korea, and Their Depositional Implication (영산강 하구의 수심 및 표층 퇴적물 특성의 변화와 퇴적환경)

  • KIM, YOUNG-GIL;CHANG, JIN HO
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.22 no.3
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    • pp.88-102
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    • 2017
  • Long-term changes in bathymetry and grain size of surface sediments were investigated for understanding depositional sedimentary environments in the channelized Yeongsan River Estuary, Korea. The results revealed that an average depth of the estuary had decreased up to 2.1 m from 1982 to 2006, while it had increased to 0.3 m from 2006 to 2012. The rapid decrease of the water depth from 1982 to 2006 was due to the vast deposition of mud caused by the change of water course and flow velocity after the estuary was dammed. Meanwhile the increase of the water depth from 2006 to 2012 may be associated with multiple erosional processes, including a dredging at the southern part of the estuary and other erosions from the dike sluice expansion work. Considering the water-depth change and tidal-level variation in the study area, an depositional rate in the estuary is estimated to be 8~9 cm/yr for the last 2 decades (1982~2006). The sediments of Yeongsan River Estuary are largely composed of silt-clay mixtures: overall, silt is distributed mainly in the shallow area of the estuary edge, while clay is confined to the deep area of the estuary center. Mean grain size of the sediments is 6.0 Ø on average in 1997, 7.8 Ø on average in 2005 and 7.7 Ø on average in 2012, respectively, suggesting that the sediments became finer due to the increase of silt and clay contents in 1997~2005. Furthermore, several lines of evidences, including the comparison between the amounts of the sediment influx discharged from the Yeongsan River and the sediments in the estuary, and the changes in distribution pattern of silt and clay contents implying that they moved from offshore to estuary dike, indicate that the mud sediments are originated mainly from the offshore, not from the river.

Drivability Monitoring of Large Diameter Underwater Steel Pipe Pile Using Pile Driving Analyzer. (수중 대구경강관말뚝의 항타관입성 모니터링을 위한 PDA 적용 사례)

  • Kim, Dae-Hak;Park, Min-Chul;Kang, Hyung-Sun;Lee, Won-Je
    • Proceedings of the Korean Geotechical Society Conference
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    • 2004.03b
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    • pp.11-19
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    • 2004
  • When pile foundation constructed by driving method, it is desirable to perform monitoring and estimation of pile drivability and bearing capacity using some suitable tools. Dynamic Pile Monitoring yields information regarding the hammer, driving system, and pile and soil behaviour that can be used to confirm the assumptions of wave equation analysis. Dynamic Pile Monitoring is performed with the Pile Driving Analyser. The Pile Driving Analyser (PDA) uses wave propagation theory to compute numerous variables that fully describe the condition of the hammer-pile-soil system in real time, following each hammer impact. This approach allows immediate field verification of hammer performance, driving efficiency, and an estimate of pile capacity. The PDA has been used widely as a most effective control method of pile installations. A set of PDA test was performed at the site of Donghea-1 Gas Platform Jacket which is located east of Ulsan. The drilling core sediments of location of jacket subsoil are composed of mud and sand, silt. In this case study, the results of PDA test which was applied to measurement and estimation of large diameter open ended steel pipe pile driven by underwater hydraulic hammer, MHU-800S, at the marine sediments were summarized.

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Fecal Solid Feed from the Recirculating Aquaculture System of the Renewable Sea Cucumber Apostichopus japonicus (해삼사료원료로서 육상순환여과양식장 고형오물의 이화학적 특징과 해삼(Apostichopus japonicus)의 소화흡수율)

  • Jeong, U-Cheol;Jin, Feng;Choi, Jong-Kuk;Md, Anisuzzaman;Choi, Byeong-Dae;Kang, Seok-Joong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.49 no.3
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    • pp.330-336
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    • 2016
  • Pollution caused by fecal solids released from recirculating aquaculture systems (RAS) is a growing global concern requiring immediate attention. Thus, this study investigated the physicochemical characteristics of fecal solid feed from RASs used for eel and rainbow trout farming. The concentrations of proteins, lipids, crude ash, and moisture in eel fecal solids were 10.9%, 1.2%, 85.8%, and 72.2%, respectively, while those in rainbow trout fecal solid feed were 20.5%, 3.2%, 70.9%, and 87.0%, respectively. The control group was fed a mixture of sea cucumber and dried sea mud. The protein digestibilities of eel and rainbow trout fecal solids were 25.43% and 23.96%, respectively, while the respective lipid digestibilities were 35.62% and 36.80%, respectively.

Geochemical Characteristics and Contamination Assessment of Surface Sediments in Lower Yeongsan River System (영산강 하류권역 하상퇴적물의 지화학적 특성과 오염평가)

  • Youn, Seok-Tai;Koh, Yeong-Koo;Oh, Kang-Ho;Moon, Byoung-Chan;Kim, Hai-Gyoung
    • Journal of Environmental Impact Assessment
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    • v.13 no.5
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    • pp.251-262
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    • 2004
  • In order to investigate the geochemical characteristics of surface sediments in lower Yeongsan river system, sediment samples from the main stream of Yeongsan river, Gomakwon and Hampyeong streams were collected and analyzed for grain size and metal and organic carbon contents. The sediment types of the streams widely vary from pebble to mud. The metal contents in the sediments are mainly dependent on grain size of the sediments, geology around the streams and organic matter contents from the domestic sewage. Enrichment factor (EF) representing the degree of metal contamination in the sediments are relatively low in the study area. But, high Zn and Pb values seem to be from the study area, partly.