• Title/Summary/Keyword: Coastal harbor

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Behavior of Currents and Suspended Sediments around a Silt Screen

  • Jin, Jae-Youll;Chae, Jang-Won;Song, Won-Oh;Park, Jin-Soon;Kim, Sung-Eun;Jeong, Weon-Mu;Yum, Ki-Dai;Oh, Jae-Kyung
    • Ocean and Polar Research
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    • v.25 no.spc3
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    • pp.399-408
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    • 2003
  • The behavior of Suspended Sediment Concentrations (SSC) around a silt screen in a microtidal coastal area was hydrodynamically measured. The current speed at the mid-layer about 30m downstream of the screen reduces to about half that at the same distance upstream. It was caused by the contraction of the vertical section due to the screen. Even during a relatively weak storm period the SSC increases to that of the value caused by dredging. Section-averaged SSC at the downstream of the screen is higher by about 60% than that at the upstream, suggesting that the silt screen plays an adverse effect rather than a constructive role in the reduction of SSC generated by dredging.

Modeling buoyant surface discharges in a shallow channel with steady flow (정상흐름하 천해역 수로에서의 저밀도수 표층방출 모델링)

  • Jung, Kyung-Tae;Jin, Jae-Youll;Park, Jin-Soon;Yum, Ki-Dai;Park, Chang-Wook;Kim, Sung-Dae;Suk Yoon
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 2002.08a
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    • pp.191-197
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    • 2002
  • The prediction of the dynamic behaviors of buoyant water discharges into a large volume of water bodies, the flows of water accompanying the density differences due to temperature differences and sometimes also to salinity differences, have attracted great concern over several decades. Heated water surface discharges from power plants and freshwater discharges in estuaries are typical examples of the buoyant flows. (omitted)

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Research on improvement measures of Harbor tranquility in Geumjin Fishing Port Excited by Incident Short Random Waves (단주기 불규칙파에 의한 금진항 정온도 개선대책 연구)

  • Chang, Sung-Yeol;Moon, Yong-Ho;Park, Won-Kyung
    • Journal of Coastal Disaster Prevention
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    • v.4 no.1
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    • pp.1-6
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    • 2017
  • Most of the short period waves are blocked by the breakwaters when the short period irregular waves propagate into the ports. However, nonlinear irregular wave numerical experiments show that the long waves generated by the nonlinear interaction is predominant in the port. Seiches phenomenon in Geumjin Fishing Port is very similar to 60 and 300 second harbor oscillations. By arranging the inner breakwater of the proper length in the inside of the port, it is possible to effectively reduce seiches, as well as the short-period wave, and significantly improve the harbor tranquility. In the case of rectangular basin type such as the Geumjin Fishing Port, the multi-directional irregular wave numerical model should be used for the investigation and countermeasures for the harbor tranquility.

Analysis of Numerical Model Wave Predictions for Coastal Waters at Gunsan-Janghang Harbor Entrance

  • Lee Joong-Woo;Lee Hak-Seung;Lee Hoon;Jeon Min-Su;Kim Kang-Min
    • Journal of Navigation and Port Research
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    • v.29 no.7
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    • pp.627-634
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    • 2005
  • Gunsan-Janghang Harbor is located at the mouth of Gum River, on the central west coast of Korea The harbor and coastal boundaries are protected from the effects of the open ocean by natural coastal islands and shoals due to depositions from the river, and two breakwaters. The navigation channel commences at the gap formed by the outer breakwater and extends through a bay via a long channel formed by an isolated jetty. For better understanding and analysis of wave transformation process where a wide coastline changes appear due to on-going reclamation works, we applied the spectral wave model including wind effect to the related site, together with the energy balance models. This paper summarizes comparisons of coastal responses predicted by several numerical wave predictions obtained at the coastal waters near Gunsan-Janghang Harbor. Field and numerical model investigations were initially conducted for the original navigation channel management project. We hope to contribute from this study that coastal engineers are able to use safety the numerical models in the area of port and navigational channel design.

An Analytical Solution of the Vertically One-dimensional Convection-Diffusion Equation for the Determination of Local Suspended Sediment Concentration (국지 부유퇴적물 농도의 결정을 위한 연직1차원 이류확산 방정식의 해석해)

  • Jung, Kyung-Tae;Jin, Jae-Youll;Kang, Hyoun-Woo;Cho, Hong-Yeon;Kim, Mee-Kyung;John Noye
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 2003.08a
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    • pp.208-215
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    • 2003
  • Convective-diffusion equations appear in various disciplines such as hydrology, chemical engineering and oceanography dealing with the transport problem of scalar quantities. Since it is nonlinear, numerical methods are generally used to obtain its solution. Very limited number of analytical solutions are available usually in cases when the convective velocity is constant or has a simple functional form (for some collection of the solutions, see Noye, 1987). There is however a continuing need to develop analytical solutions because of its practical importance. Analytical solutions of the convection-diffusion equation are valuable not only for the better understanding on the transport process but the verification of numerical schemes. (omitted)

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A Review of Measures against Environmental Impact of Suspended Sediments Generated by Coastal Development Works (연안개발공사로 인한 부유토사의 환경 악영향 저감방안 고찰)

  • Song, Won-Oh;Jin, Jae-Youll;Chae, Jang-Won;Ahn, Hee-Do;Maeng, Jun-Ho;Oh, Jae-Kyung
    • Ocean and Polar Research
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    • v.25 no.spc3
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    • pp.409-416
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    • 2003
  • Coastal development works generally increase the suspended sediment concentration of the ambient water, causing environmental impacts in various manners. The most active measures in three sides have been reviewed for their applicabilities in Korea. Referring to the cases in the USA, the legislation of environmental windows seems to be not proper for Environmentally Sound and Sustainable Developments (ESSD) until sufficient scientific data are obtained to address the individual issues of potential negative impacts. Feedback monitoring can be regarded as the best way for ESSD. Korea also has the basic legal system for the feedback monitoring as well as Environmental Impact Assessments (EIA). However, the frequency, period and parameter of related surveys should be improved for the true ESSD. Moreover, environmental facilities such as environmental dredgers should be widely used for mitigating environmental Impacts caused by coastal development works.

On the Limitation of Turbidity Generation Unit

  • Jin, Jae-Youll;Park, Jin-Soon;Song, Won-Oh;Oh, Jae-Kyung
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 2003.08a
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    • pp.363-368
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    • 2003
  • Quantification of sediment losses into the ambient waters associated with various works of coastal developments is highly required for predicting their possible detrimental impacts on the aquatic environments. Although there have been some studies especially related to dredging (e.g., Nakai, 1978; Kirby and Land, 1991; Collins, 1995; Pennekamp et al., 1996; Lorenz, 1999; Jin et al.,2003), none can be regarded as a general guidance up to date, which results from the facts that the amount of sediments released into the ambient waters is influenced by several site/case-specific conditions, and that the existing studies have been carried out using different methods. (omitted)

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