• 한국해안해양공학회지
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• 제13권1호
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• pp.1-8
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• 2001

파랑으로 인해 발생되는 흐름은 연안에서 질량수송의 일련의 과정을 야기시키므로 연안유역의 관리에 파랑과 흐름의 상호작용에 대한 정확한 이해가 요구된다. 본 논문은 적응가능한 사면 구조 격자에 근간을 둔 파랑장과 흐름장을 혼합한 수치모델을 기술하였다. 사용한 모델은 쇄파, 천수, 굴절, 회절, 파랑과 흐름의 상호작용, 평균해면의 저하와 상승, 혼합 과정, 바닥 마찰 효과 그리고 해안선에 접한 운동 등을 해석할 수 있다. 주기와 수심으로 평균한 지배 방정식은 단계적으로 엇갈린 사면구조 격자에 적응 가능한 Adam-Bashforth 2차 유한 차분 기법으로 양해적으로 모델화 되었다. 본 모델로부터의 결과는 평면 해변에서 경사 입사파에 의해 발생된 연안류의 실험치와 타당한 일치를 보였다.

• 한국항해항만학회지
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• 제32권4호
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• pp.305-313
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• 2008

Recently it was known that the problems of nearshore processes and damage of berth and counter facilities frequently had appeared at the small fishery port, such as Daebang near Samcheonpo city, Korea. Here we try to analyze the impact of the rearrangement of counter facilities and berth layout adopted for tranquility of its inner harbor. Because this harbor is being connected to Daebang channel, the rearrangement of the structures might affect to the current speed and direction and wave height, so do to the sea bottom undulation. Therefore, we made model test for the several layouts of the berth and breakwater in this area. Numerical model result shows that the bottom was eroded by 1m by tidal currents and the speed of flow did not shrink, even after the construction work was completed. The direction of the sand movement was downdrift. Although the model study gave reasonable description of beach processes and approach channel sedimentation mechanism, it is necessary to compare with the field history, including the records of waves, tides and bottom materials, etc. for better prediction.

• 한국지형학회지
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• 제24권3호
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• pp.133-147
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• 2017

This study investigated the cases of relative location, especially focused on the geomorphological situation, for the conceptualization of the location knowledge. In order to perform this study, first of all, I approached meaning of location. In this study I used the terms 'site' and 'situation'. 'Site' as used here means the location of a given place with its local internal features or resources. 'Situation' refers to the location of place as related to other places. As to location, no place exists in isolation. Therefore, it is necessary to look beyond the internal nature of the area itself to perceive its external relations with other areas. The examples of geomorphological situation were focused on the scale linkage of the examples, the interaction between elements of earth surface processes, and the method of comparative region. The regions of examples were the landscape of Mt. Hymalaya to Bengal deep sea fan, the climatical difference of continental east and west, the landscape of Mt. Geum & Sangju beach, the landscape of the south and north face of Mt. Mai., Hamjibaakgol asymmetrical valley, and the landscape of inland sea and outer sea type island.

• 한국항만학회지
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• 제13권1호
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• pp.155-166
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• 1999

The construction of the coastal structures and reclamation work causes the circulation reduced in the semi-closed inner water area and the unbalanced sediment budget of beach results in an alteration of beach topography. Among the various fluid motions in the nearshore zone water particle motion due to wave and wave-induced currents are the most responsible for sediment movement. Therefore it is needed to predict the effect of the environmental change because of development and so the prediction of wave transformation dose. The purpose of this study is to introduce the relation between waves wave-induced currents and sediment movement. In this study we will show numerical method using energy conservation equation involving reflection diffraction and reflection and the surfzone energy dissipation term due to wave breaking is included in the basic equation. For the wave-induced current the momentum equation was combined with radiation stresses lateral mixing and friction Various information is required in the prediction of wave-induced current depending on the prediction tool. We can predict changes in wave-induced current from the distribution of wave especially near the wave breaking zone. To evaluate these quantities we have to know the local condition of waves mean sea level and so on. The results from the wave field and wave-induced current field deformation models are used as input data of the sediment transport and bottom change model. Numerical model were established by a finite difference method then were applied to the development plan of the eastern Pusan coastal zone Yeonhwa-ri and Daebyun fishing port. We represented the result with 2-D graphics and made comparison between before and after development.

• 해양환경안전학회지
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• 제14권4호
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• pp.333-338
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• 2008

해안 지역은 해수의 운동에너지의 대부분은 해안에서 소산되며 이 과정에서 해안의 토사 등이 유실된다. 수면에 돌출된 방파제에 비해 수중구조물은 해수의 유통을 가능하게 하고 해안선을 따라 해수순환을 가능케 한다. 이 연구에서는 해안 침식을 방지 기능을 갖는 수중구조물을 하부틈새를 갖는 수중장애물로 형상화 하고 후방의 흐름특성을 규명하였다. 실험은 Re =$1.2{\times}10^4$ 조건에서 2프레임 입자영상유속계를 이용하여 속도장을 계측하여 고찰하였다. 측정된 시간평균 속도분포를 분석한 결과 유선의 곡률 효과가 현저히 나타났으며 전단층 주위 유체의 유입 등의 영향으로 박리 전단층 내에서 커다란 와구조가 연속적으로 발생하였다. 또한 하부틈새의 크기가 증가할수록 재순환 영역의 중심이 후류로 이동하고 재순환영역의 강도도 약해지는 결과를 보였다.

• Ocean Systems Engineering
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• 제8권1호
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• pp.1-20
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• 2018

The target area of the proposed study, Mamaia beach, is a narrow stretch of sand barrier island that sits between the Siutghiol Lake and the Black Sea. In the northern part of the bay, is located the Midia Port, where between 1966 and 1971 a long extension of 5 km of the offshore was built. Because of this extension, the natural flow of sediments has been significantly changed. Thus, the southern part of the Mamaia Bay had less sand nourishment which meant that the coast was eroding and to prevent it a protection of six dikes was built. After approximately forty years of coastal erosion, the south of the Mamaia Bay had in 2016 a new protection scheme, which includes first of all the beach nourishment and a new dike structure (groins scheme for protection) to protect it. From this perspective, the objective of the proposed study is to evaluate the effectiveness of the old Master plan against the new one by modeling the outcome of the two scenarios and to perform a comparison with a third one, in which the protection dikes do not exist and only the artificial nourishment has been done. In order to assess the wave processes and the current patterns along the shoreline, a complex computational framework has been applied in the target area. This joins the SWAN spectral phase averaged model with the 1D surf model. Furthermore, new UAV technology was also used to map out, chart and validate the numerical model outputs within the target zone for a better evaluation of the trends expected in the shoreline dynamics.

• 한국지형학회지
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• 제26권1호
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• pp.59-78
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• 2019

The physical and chemical characteristics of more than 5 m sandy deposits behind the beach in Sinji-do Island are investigated and its burial ages are estimated using Optically Stimulated Luminescence. By the estimated burial ages of the sandy deposits, this section is divided into four sub-units: Unit I (6.2 ka), Unit II (23.2 ka), Unit III (115.9 ka), and Unit IV (115.9 to 127.5 ka). It can be proposed that the Unit I of a coarse sand deposited during the Holocene Climatic Optimum. Unit II, supposed to be the aeolian sediments, formed during the Last Glacial Maximum (LGM). It can be supposed that the study area was not affected by the marine processes during the LGM, directly. Unit III is more consolidated deposits of coarse silt to fine sand and deposited during the Last Interglacial Period. Unit IV mainly consist of beach gravels with sandy matrix deposited during the Marine Isotope Stage 5e (MIS 5e), and thus indicates that the sea level of the southwest sea had risen 3 to 5 m above present sea level during the MIS 5e.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2015년도 춘계학술대회
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• pp.338-339
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• 2015

VTS 의사결정지원시스템은 관제사들이 선박을 관제함에 있어서, 의사결정을 지원하기 위하여 선박 간 거리 등의 정보를 제공하는 시스템을 의미한다. 본 논문에서는 현재 제정되고 있는 IALA 표준을 중심으로 VTS 의사결정지원 시스템의 구분, 제공하는 경고 정보의 세분화된 정의, 제공되어야 할 경고 기능 등을 분석한다.

• 한국패류학회지
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• 제31권3호
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• pp.221-232
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• 2015

Observations in beach, intertidal and upper subtidal environments in Peter the Great Bay (north-western East Sea) have shown that attached algae were found on empty shells of 13 species of epifaunal and infaunal bivalve mollusks. Thirteen algae species were identified on empty dislodged shells but more than 50 species are known to be epibiotic on living bivalves. The dislodgement of shells with attached algae takes place in semi-enclosed, low-energy areas, as well as those which are open and affected by strong wave action, indicating the large scale of this phenomenon. The significance of seaweed transportation of living mollusks and their empty shells in the coastal zone, involving both taphonomic and ecological processes, is stressed. Algae appear to be a taphonomic agent and play a similar role as compared to birds or hermit crabs, but they act passively and contribute to environmental mixing in death assemblages in coastal environments.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.648-653
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• 2003

Optimized recovery of heavy minerals from the near shore sands of Korean Yellow Sea was investigated using physical processing technologies such as gravity concentration and magnetic separation. The head samples were subjected to the three stages effective separation; Head sample was first treated by a spiral separator to recover rough heavy mineral concentrates, which are contained minerals like ilmenite, zircon and rare earth minerals. Much higher beneficiation processes were subsequently taken by wilfley table and magnetic separation according to their magnetic field responses. Heavy minerals were effectively recovered by wilfley table and subsequent recleaning of heavy minerals by magnetic separations was conducted. Qualitative and relative-quantitative analyses of their constituent elements were doing using XRD and XRF.