다수의 부체로 지지된 초대형 해양구조물에 작용하는 정상표류력 (Ⅱ)

이창호,홍사영,구자삼,조효제,김경태 韓國海洋大學校 附設 海洋科學技術硏究所 1997 硏究論文集 Vol.5 No.-

본 논문에서는 파중에서의 다수의 3차원 임의형상 부체에 의해 지지된 초대형 해양구조물에 작용하는 정상표류력 해석법을 제시한다. 3차원 특이점 분포법, 파의 상호간섭이론, 운동량 이론에 의한 Far field 법과 3차원 골조구조를 다루기 위한 유한요소법을 결합하여 이론을 정식화하였으며, 수치계산 결과를 Kagemoto [6]에 의한 33(3행11렬)개의 footing형 축대칭 부체에 의해 지지된 해양구조물에 작용하는 정상표류력의 실험치 및 계산치와 서로 비교 검토함으로써 본 해석법의 타당성을 검정하였다. A numerical procedure is described for predicting steady drift forces on very large offshore structures supported by a large number of the floating bodies of arbitrary shape in waves. The developed numerical approach is based on a combination of the three-dimensional source distribution method, the wave interaction theory, the far-field method of using momentum theory and the finite element method for structurally treating the space frame elements. Numerical results are compared with the experimental or numerical ones, which are obtained in the literature, of steady drift forces on a offshore structure supported by the 33 (3 by 11) floating composite vertical cylinders in waves. The results of comparison confirmed the validity of the proposed approach.

海洋景觀을 考慮한 海洋建築計劃에 關한 硏究

李漢錫 韓國海洋大學校 附設 海洋科學技術硏究所 1998 硏究論文集 Vol.7 No.-

There are numerous structures linked with the sea. They are standing on the water's edge in the waterfront area or ocean space. The most important one of them is oceanic architecture. Oceanic architecture is architectural space created by directly or indirectly using the features of the waterfront or ocean in the design. Therefore the quality of seascape(or oceanscape) can be greatly influenced by the oceanic architecture. In this paper the characteristics and planning of seascape are examined. Especially recommendations for planning of seascape are dealted with each category of seascape, and then on the basis of them architectural design guidelines are suggested for creating good quality of seascape.

다방향 불규칙파중의 초대형 해양구조물의 동적응답해석

구자삼,조효제,김경태 韓國海洋大學校 附設 海洋科學技術硏究所 1997 硏究論文集 Vol.6 No.-

본 논문에서는 3차원 특이점분포법, 파의 상호간섭이론 및 유한요소법을 결합한 Goo등[29]이 개발한 초대형 해양구조물의 동적응답 해석법과 스펙트럴 해석법을 이용하여 다수의 임의형상 지지부체간의 유체역학적 상호간섭을 고려한 다방향 불규칙파중의 초대형 해양구조물의 운동응답 및 구조응답의 유의치를 동시에 계산할 수 있는 동적응답 해석법을 개발하였으며, 반잠수식 Ring 형상의 초대형 해양구조물을 수치계산 모델로 하여 구조물의 동적응답에 미치는 상호간섭과 다방향파의 영향을 평가하였다. A numerical procedure is described for predicting the motion and structural responses of the very large floating offshore structures supported by multiple 3-D floating bodies of arbitrary shape in multi-directional irregular waves. The developed numerical approach taking into account of the hydrodynamic interactions among the multiple floating bodies is based on a combination of the 3-D source distribution method, the wave interaction theory, the finite element method and the spectral analysis method to get the significant values of the dynamic responses in the multi-directional irregular waves. The effects of wave interactions and directionality on the dynamic responses of a very large offshore structure, which is semisubmersible ring type, are numerically examined.

거리의존 해양환경에서 수동소나체계의 표적탐지거리예측

김태학,김재수 韓國海洋大學校 附設 海洋科學技術硏究所 1997 硏究論文集 Vol.6 No.-

원거리에서 수동소나에 의한 탐지거리를 예측하기 위해서는 소나방정식이 이용된다. 본 연구에서는 거리와 깊이함수의 신호이득 및 탐지확률을 구한 후 이를 거리로 적분하여 거리의존 해양환경에서 탐지거리를 계산하는 탐지거리 예측모델을 개발하였다. 개발된 모델은 기존에 발표된 거리독립 해양환경에서의 결과와 비교하여 검증하였고, 이를 바탕으로 거리의존 해양환경에서 수동소나에 의한 표적탐지에 큰 영향을 주는 나수성 소용돌이 해양환경에 확장 적용하여 표적의 탐지거리를 예측하였으며, 그 결과에 대하여 소개한다. The prediction of detection range of a passive sonar system is essential to estimate the performance and to optimize the operation of a developed sonar system. In this paper, a model for the prediction of detection range in a range-dependent ocean environment based on the sonar equation is developed and tested. The prediction model calculates the transmission loss using PE propagation model, signal excess, and the detection probability at each target depth and range. The detection probability is integrated to give the estimated detection range. In order to validate the developed model, two cases are considered. One is the case when the target depth is known. The other is the case when the target depth is unknown. The environment. Also, the developed model is applied to the range-dependent ocean environment where the warm eddy exists. The computational results are shown and discussed. The developed model can be used to find the optimal frequency of detection, as well as the optimal search depth for the given range-dependent ocean environment.

Shoreline Change Based on Long Term Wind Statistics in Suyeong Bay

Kang,Hyo Jin 韓國海洋大學校 附設 海洋科學技術硏究所 1994 硏究論文集 Vol.3 No.-

연안 퇴적물 이동에 의한 수영만의 광안리와 해운대 지역의 해안선 변화를 조사하였다. 이 지역에 가장 큰 영향을 미칠 것으로 추정되는 동쪽과 남쪽 사이에서 부는 바람의 15년간 풍향별 발생 빈도를 이용한 월별 평균 풍향과 풍속을 계산하여 JONSWAP법에 의한 심해 유의파를 추정하고, 굴절 및 천수효과에 의한 쇄파고와 쇄파각을 계산하였으며, 그에 의한 연안 퇴적물 이동량을 계산하고 퇴적물 이동량의 수급에 따른 해안선의 변화를 계산하였다. 광안리 지역에서는 주된 연안 퇴적물 이용이 남서에서 북동방향으로, 해운대 지역에서는 동쪽에서 서쪽으로 이동하는것으로 나타났으며, 광안리 지역의 해안선은 북동쪽이 전진, 남서쪽이 후퇴하는 양상을 보이고, 해운대 지역은 동쪽이 후퇴, 서쪽이 전진하는 결과를 보이고 있다. Shoreline change due to the littoral drift in Suyeong bay, especially the Gwanganri and Haeundae beaches, was investigated. Average monthly frequency, speed, and direction of winds blowing from between east and south for the last 15 years were analysed, and offshore significant waves were hindcasted using the JONSWAP model. Wave refractions, shoaling, and breaking were also investigated for the calculation of littoral drift. At the Gwanganri beach major longshore transport of sands occurs from the southwest to the northeast and the shoreline seems to advance in the northeast while it recedes in the southwest. At the Haeundae beach the sands mainly move from the east to the west and the shoreline retreats in the east and advances in the west.

빙쇄굴 : 해저지반 상호작용 모델 비교연구 Seabed Interaction Models

최경식,이종호 韓國海洋大學校 附設 海洋科學技術硏究所 2001 硏究論文集 Vol.10 No.2

The interaction of grounded ice ridges with underlying seabed is one of the major considerations in the design of Arctic pipeline systems. Previously several ice scour models were developed by researchers to describe the ice scour-seabed interaction mechanism. In view of possible improvements, a comparative study of those ice scour models is performed and their limitation in modeling is discussed. Simple laboratory tests are carried out and then the shape pattern of deposited soil around the ice model is newly defined. unlike the rectangular idealization of an ice block, in this modified ice scour model, trapezoidal cross sections are assumed to represent the typical shape of an ice ridge based on the field observation data. With the horizontal and vertical motion of ice model, the ice scour depth and soil reacting forces on seabed are calculated with varying the keel angle of an ice ridge model.

프레임형 해양구조물의 보치환 기법에 관한 연구

박춘군,박한일 韓國海洋大學校 附設 海洋科學技術硏究所 1999 硏究論文集 Vol.8 No.-

For offshore structures, dynamic analysis becomes increasingly important as water depth increases and structural configuration becomes more slender. In the case of dynamic analysis of frame structures, much computer time and high cost are required due many degrees of freedom. In this paper, a new technique of permutating a segment of frame structure to a beam is developed, which is called here Beam permutation Technique. The technique is based on definition of stiffness matrix of the beam which is obtained by defining the actions(or forces) required to obtain unit translation or rotation for each degree of freedom with all other degree of freedom restrained to zero displacement or rotation. In the technique, and assumption si made that relative positions of nodes in the ends of the segment are not variable. The technique can significantly reduce the degrees of freedom of frame structures and thus the computing time in dynamic analysis. The natural frequencies and static displacements of the permutated beam are obtained and compared to those of ANSYS with a good agreement.

ALGAL PIGMENTS AND THEIR DEGRADATION PRODUCTS IN SUSPENDED AND SINKING PARTICULATE MATERIAL IN THE GULF OF MEXICO

NOH,Il 韓國海洋大學校 附設 海洋科學技術硏究所 1994 硏究論文集 Vol.3 No.-

Photosynthetic pigments and their degradation products in suspended and sinking particles collected from the Gulf of Mexico waters 1987-88, were measured using High Performance Liquid Chromatography (HPLC). The short term variations in flux rates of chlorophylls and carotenoids as well as their degradation products were compared at the mesoscale cyclonic and anticyclonic circulation features (cold core ring and warm core ring). Chlorophyll a was the predominant porphyrin of suspended particulate matter at both CCR and WCR. Among carotenoid pigments, 19' hexanoyloxyfucoxanthin, which is a biomarker of prymnesiophytes, was dominant pigment at both rings. Phaeophorbide a, which is produced through the grazing processes of grazers, was the predominant degraded pigment in sinking particles at the study area. Total pigment flux in CCR was an order of magnitude higher than that in WCR. Less than 1% of the standing stock of the pigments measured sank out of the upper 200 m of the WCR on any given day. Thus, suspended particulate matter in Gulf of Mexico was not recycled rapidly.

沿岸에서 複合住居團止計劃에 關한 硏究

李漢錫,金丙坤,朴健 韓國海洋大學校 附設 海洋科學技術硏究所 2002 硏究論文集 Vol.11 No.1

It is required to create 'living complex' at the coastal areas and coastal suburbs to meet the increasing demands for the living space, as well as tourism, culture and leisure activities. The purpose of this study is to plan three types of the 'living complex' at the coastal areas. This is a kind of pilot planning which provides design models of the living complex from the architectural design and planning standpoints.

산업 잠수 기술의 발달 : 혼합기체를 중심으로

강신영,김도현 韓國海洋大學校 附設 海洋科學技術硏究所 1992 硏究論文集 Vol.1 No.1