• 한국해양공학회지
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• 제12권3호통권29호
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• pp.75-85
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• 1998

A finite difference model for predicting time-dependent, wave-induced nearshore current is studied. The model includes wave refraction, wave-current interaction, bottom friction and wind effect. This model iteratively solved the linear the linear set of conservation of both mass and momentum, which were time averaged (over one wave period) and depth integrated, for mean velocities and free surface displacement. Numerical simulations of nearshore current under oblique wave attack, and for wave and wind induced current on a longshore periodic beach are carried out. Longshore velocities tend to zero in some distances outside the breaker line. And the peak velocity is shifted shoreward at the breaker line. The results represent the general characteristics of the nearshore current induced by wave.

• 한국패션뷰티학회지
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• 제3권3호
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• pp.56-63
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• 2005

In the study of permanent waving method after mixing ample and permanent wave solvent in permanent wave the dyed humans hair are as follows; First, Permanent waving method after mixing ample and permanent wave solvent is that the better effective way in permanent wave the dyed humans hair because permanent waving cycle is constant and hair cuticle is glossy. Second, This study is not interpret in permanent wave dyed humans hair that tensile strength is effect of permanent waving method after mixing ample and permanent wave solvent. A extension degree is effect of permanent waving method after mixing ample and permanent wave solvent use indifferent ample treatment method. Third, Hair cuticle damages are a little permanent waving method after mixing ample and permanent wave solvent in permanent wave dyed humans hair.

• 대한조선학회논문집
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• 제38권1호
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• pp.37-42
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• 2001

본 논문에서는 유연한 그물 구조로 된 새로운 개념의 소파 장치를 제안한다. 본 연구를 하게된 동기는 이미 알려져 있는 기존의 소파장치들이 작은 파수조에서는 제대로 그 역할을 하지 못한다는 점에서 시작되었다. 소파기의 성능을 파악하기 위하여 소파기의 길이와 소파기의 면적을 변화시켜 여러 가지 파장의 파에 대해서 실험을 수행하였다. 실험 결과 제안된 소파 장치는 그 길이가 짧은 파수조에서도 뛰어난 성능을 발휘함을 알 수 있었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.792-797
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• 2003

A helical vane is applied to reduce the magnitude of the impulse wave discharged from the exit of a duct. A shock tube with an open end is used to investigate the effect of the helical vanes on the impulse wave magnitude. Four different types of helical vanes are installed into the low-pressure tube of shock tube. The magnitude of the incident shock wave is varied below 1.25, and the magnitude of impulse wave is measured using a pressure transducer mounted on a wedge probe. Instant images of the impulse wave are obtained by means of the Schlieren optical method. The present experimental results show that the helical vane considerably reduces the magnitude of the impulse wave and the vane effects are more remarkable for stronger incident shock wave.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.544-549
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• 2003

When a shock wave arrives at an open end of tube, an impulse wave is discharged from the tube exit and causes serious noise and vibration problems. In the current study, the effect of the cross-sectional area of tube on the impulse wave is numerically investigated using a CFD method. The Harten-Yee's total variation diminishing(TVD) scheme is used to solve the axisymmetric, two-dimensional, unsteady, compressible Euler equations. With three different cross-sectional areas of tube, the Mach number of the incident shock wave $M_{s}$ is varied between 1.01 and 1.5. The results obtained show that the directivity and magnitude of impulse wave strongly depend upon the Mach number of incident shock wave and are influenced by the tube area. It is also known that the tube cross-sectional area significantly affects the magnitude of impulse wave at or near the tube axis.

• 산업기술연구
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• 제27권A호
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• pp.9-14
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• 2007

This study was designated to clarify the aspect of the wave propagation around the cavity. The change of traveltime and amplitude of the seismic wave was observed according to the various wave velocities of the cavity. The seismic wave detour or penetrate the cavity depending on the seismic velocity of the in-filled material. Generally, seismic wave detours toward high velocity zone around the cavity, and when the velocity of the cavity material reaches to 80 % of the base rock, the wave penetrates the cavity. The traveltime of the detouring seismic wave is not sensitive to the change of the cavity velocity, but as the velocity of the cavity increases, the fall of the amplitude was reduced. The penetrating wave showed the steeply increasing amplitude due to the reiteration of the detouring wave.

• 한국해양공학회지
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• 제26권2호
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• pp.68-78
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• 2012

This study proposes an improved 3-D model that includes a new non-reflected wave generation system for oblique incident and multi-directional random waves, which enables us to estimate the effect of the various wave-types on 3-D wave fields in a coastal area with permeable submerged breakwaters. Then, using the numerical results,the three-dimensional wave field characteristics around permeable submerged breakwaters are examined in cases of oblique incident and multi-directional random waves. Especially, the wave height, mean surface elevation and mean flow around the submerged breakwaters are discussed in relation to the variation of incident wave condition.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2006년도 임시총회 및 하계학술연구발표회
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• pp.106-107
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• 2006

• Journal of Advanced Marine Engineering and Technology
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• 제35권5호
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• pp.682-689
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• 2011

최근 우리나라 해안지역에서는 너울성 파도(Swell-like wave)에 의한 재해가 빈번하게 발생하고 있다. 이러한 해양 현상은 풍파(wind wave)에 비해 주기가 10초대 이상의 긴 주기를 갖는 특성이 있다. 장주기 파(Long period wave)에 의한 피해를 사전에 예방하기 위해서는 실시간으로 정확하게 관측할 수 있어야 한다. 하지만 현재 파고를 측정하는 기기는 풍파를 관측하는 것을 주 목적으로 하고 있어 장주기 파를 관측할 수가 없다. 따라서 본 연구에서는 GPS를 이용하여 해양에서 실시간으로 운영할 수 있는 장주기 파고 관측시스템을 개발하고자 하는 것이다.

• 한국해양공학회지
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• 제27권4호
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• pp.55-61
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• 2013

The numerical simulation using LES-WASS-3D is developed to investigate the wave run-up on the revetment along the canal. Interaction of ocean wave, current, and Kelvin wave is investigated on 40 conditions varying the number of ship, cruising direction, and relative cruising location of ships, when a 650TEU container cruises in the canal. The mean wave run-up heights on the revetment are compared for every simulated conditions. The largest height of wave run-up is generated at the C-pair condition and the wave run-up generated at the canal entrance is larger than that at the inside canal. When Kelvin waves is interacted with the current, the mean wave run-up height is increased approximate 10% compared with no current condition.