• 한국해안해양공학회지
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• 제13권3호
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• pp.202-208
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• 2001

현재 실무에서 많이 적용되고 있는 Saville의 가상 구배법에 기초하여 복합사면에서의 도파고를 간단히 산정하기 위한 양해적 근사식을 개발하였다. 수심대 파고비, 사면경사, 파형경사 등과 도파고비와의 관계를 도출하였다. 또한 도파고 산정에 있어 정확도를 검증하기 위하여 양해적 근사식의 산정결과를 Saville의 관측결과와 네덜란드 Delft 공식의 산정결과와 비교하였다.

• 한국해양공학회지
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• 제18권1호
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• pp.16-21
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• 2004

In general, core materials of rubble mound breakwater are used at a restricted range of 0.015㎥～0.03㎥. However, it is not satisfied with the standard design in over fifty percent of the cases. In this study, model tests and numerical analysis are employed to examine the range of core material that has no problem with capacity maintenance and stability of rubble mound breakwater. Model tests measure the porosities that are mixed in various ratios, to classify core materials by three parameters. The slope stability of rubble mound breakwater is investigated, using numerical analysis, with a friction angle and a unit weight. The change of unit weight, which is followed by the mixed rate of size core material, has no large affect on slope stability, and there is no problem with ensuring slope stability of the rubble mound breakwater.

• 대한토목학회논문집
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• 제28권2B호
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• pp.249-259
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• 2008

본 연구에서는 투과성잠제의 비탈면경사가 주변 파동장에 미치는 영향을 검토하기 위해 투과성구조물에 의한 유체저항(관성저항, 층류저항 및 난류저항)을 고려할 수 있는, 즉 파-구조물-지반의 상호작용을 해석할 수 있는 수치모델에 LES 난류모델을 도입한 새로운 수치해석기법(LES-WASS-2D)을 제안하여 기존에 수행되었던 수리모형실험과의 비교를 통하여 검증하였다. 이러한 수치해석기법을 이용하여 투과성잠제의 비탈면경사의 변화에 대한 수치모의를 수행한 결과, 비탈면경사가 완만해질수록 반사율 및 투과율이 감소함과 동시에 에너지손실(Energy loss)이 커지는 것을 알 수 있었다. 또한, 잠제의 비탈면경사의 변화에 따른 마루에서 쇄파점의 위치 및 잠제 배후에서의 순환류와 평균와도의 규모에 대해서도 논의하였다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2001년도 추계학술대회 논문집
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• pp.138-143
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• 2001

Based on mild slope equation and parabolic approximation the forward diffraction of monochromatic waves by a straight breakwater are studied numerically. The characteristics and effects of stem wave along breakwater and the relations between the stem wave and incident wave angle are discussed.

• 한국해안해양공학회지
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• 제16권2호
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• pp.103-107
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• 2004

파활동경사라는 새로운 무차원 수를 도입하여 소파제의 중량 산정식을 개발하였다. van der Meer(1987)는 Iribarren 수를 도입하여 중량 산정식을 개발하였는데 조건에 따라 전혀 다른 분포경향을 보였다. 반면에 파활동경사를 도입한 산정식은 조건에 관계없이 동일한 분포경향을 보였으며, 비례상수를 Iribarren 수의 함수로 취하였을 때 매우 높은 정밀도를 갖는 경험식을 도출하였다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제12권1호
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• pp.283-296
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• 2020

A numerical model is established to investigate the run-up of a solitary wave after propagating over a triangular saw-tooth-shaped submerged breakwater. A rectangular-shaped submerged breakwater is simulated for comparison. Several factors, including the submerged depth, the lagoon length and the beach slope, are selected as independent variables. The free surface motions and velocity fields of the solitary wave interacting with the submerged breakwater are discussed. The results show that the submerged depth and lagoon length play significant roles in reducing the run-up. The influence of the beach slope is not significant. At the same submerged depth, the triangular saw-tooth-shaped submerged breakwater has only a slightly better effect than the rectangular-shaped submerged breakwater on the run-up reduction. However, a calmer reflected wave profile could be obtained with the rougher surface of the saw-tooth-shaped submerged breakwater. The study conclusions are expected to be useful for the conceptual design of saw-tooth-shaped submerged breakwaters.

• 한국정보통신학회논문지
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• 제16권3호
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• pp.440-447
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• 2012

천수변형, 굴절, 회절, 반사, 쇄파에 의한 에너지감쇠를 모두 고려한 시간의존완경사방정식을 이용하여 50년 빈도 설계파 내습시 매립과 방파제 설치에 따른 파랑변형 수치실험을 수행하였다. 항의 입구에서 입사되는 파랑은 만내부로 진입하는 과정에서 바닥에 의한 에너지 감쇠와 쇄파 작용 등으로 인해 파고의 점진적 감소가 나타났다. 매립후 75 m의 방파제를 설치하였을 경우 방파제 배후에서 파고분포는 29~128 cm 범위로 일부 해역에서 항만 정온도가 확보되는 것으로 나타났다. 보다 넓은 해역에서 정온도를 확보하기 위해서는 방파제의 길이를 100 m 이상 확장하는 것이 타당할 것으로 판단된다. 그리고, 방파제를 설치하였을 경우 방파제 배후에서 파고는 80% 이상 감소하였다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제3권2호
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• pp.122-125
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• 2011

In this work, the movement pattern of a floating breakwater is numerically analyzed using Smoothed Particle Hydrodynamic (SPH) method as a Lagrangian scheme. At the seaside, the regular incident waves with varying height and period were considered as the dynamic free surface boundary conditions. The smooth and impermeable beach slope was defined as the bottom boundary condition. The effects of various boundary conditions such as incident wave characteristics, beach slope, and water depth on the movement of the floating body were studied. The numerical results are in good agreement with the available experimental data in the literature The results of the movement of the floating body were used to determine the transmitted wave height at the corresponding boundary conditions.

• 한국해양공학회지
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• 제15권1호
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• pp.7-11
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• 2001

In this paper, trapezoid sections and prominence sections were examined to improve the performance of floating breakwater in long waves. The linear potential theory is used and the boundary element method with a matching boundary is employed for numerical computation. The effects of the side slope of the trapezoid section and the geometry ratio of the prominence section on the floating breakwater were examined. It was found that trapezoid sections show lower transmission coefficients than the rectangular sections in the long wave range. In prominence sections the size of the sides are more important than the size of the top. Proper choices of the pontoon type geometry may move the local minimum point of the wave transmission coefficient toward the longer wave ranges and improve the performance of the floating breakwater in the long wave range for a given wave period.

• 한국해양공학회지
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• 제24권1호
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• pp.106-115
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• 2010

This study described the stability of riprap, which was examined by a two-dimensional physical model of a scattered riprap submarine breakwater. Artificial reef structures made of scattered riprap are used like artificial intertidal zone structures as waterfront seaside structures. To prevent topography change in such an artificial intertidal zone the energy is reduced at the scattered riprap submarine breakwater by intercepting high waves. The breaking waves are converted into flow on the front surface slope of the submarine breakwater, which follows the upper part of the artificial intertidal zone. Because of this phenomenon of resisting water flow, it is very important to calculate the required weight of the riprap to maintain its stability. The results of a physical model can be abstracted as shown below. First, distribute the wave breaking types occurring on the front surface slope of the submarine breakwater and arrange it in relation to the movement of riprap. Second, using the hydraulic phenomenon that occurs at the depth of the scattered riprap submarine breakwater, propose a calculation formula for the velocity distribution showing the influence on the stability of the riprap. Third, propose and compare values, which can be obtained by experiments and calculations for riprap stability on the front surface of the artificial intertidal zone. Fourth, calculate the required weight for riprap stability.