• 화약ㆍ발파
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• 제36권2호
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• pp.27-35
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• 2018

기존 수중발파와 달리 잠수부에 의존하지 않고 바지선위에서 천공, 장약, 발파 등 수중발파작업의 전 과정이 바지선 상부에서 이루어 질 수 있도록 완전수밀이 가능한 수중발파용구조체를 제안 및 제작하였다. 이 구조체를 이용한 수중발파와 기존 수중발파의 결과를 비교하여 현장 적용성 및 효용성을 검증하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.705-710
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• 2002

Welding is used not only during the shipbuilding, but also during the repairing of ships. While repairing of ships, it is inevitable to weld new materials with degraded materials. In this case, it is predicted that the strength of both the sections is not identical each other. In this study, the respective welded joints in terms of mechanical properties such as microstructure, mechanical strength and fatigue crack propagation, with the component obtained from the barge used for a long-term period, were analyzed. It was found that the material degradation had a significant effect on the welded joints. The fatigue crack propagation in welded sections showed a big difference. The rate of fatigue crack growth of degraded material for both heat affected zone and parent metal was faster than that of new material. By contrast, The result within identical materials showed that the heat-affected zone was slower than that of parent metal

• 한국정밀공학회지
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• 제19권11호
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• pp.75-82
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• 2002

Welding is used not only for the shipbuilding, but also for the repairing of ships. While repairing of ships, it is inevitable to weld new materials with degraded materials. In this case, it is predicted that the strength of both the sections is not identical each other. In this study, the respective welded joints in terms of mechanical properties such as microstructure, mechanical strength and fatigue crack propagation, with the component obtained from the barge used for a long-term period, were analyzed. It was found that the material degradation had a significant effect on the welded joints. The fatigue crack propagation in welded sections showed a big difference. The rate of fatigue crack growth of degraded material for both heat affected zone and parent metal was faster than that of new material. By contrast, the result from identical materials showed that the rate of fatigue crack growth of the heat-affected zone was slower than that of parent metal.

• 한국해양공학회지
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• 제17권2호
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• pp.21-26
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• 2003

The reel-lay method of submarine pipelines a continuous string of pipe coiled onto a reel. Assembly of this pipe that is string is accomplished onshore by welding, and nondestructive testing is carried out prior to coiling the pipe. The total length of pipes on the reel depends on the reel and pipe diameters. Pipeline installation is accomplished by uncoiling, straightening the pipe, and laying out the pipe string onto the seabed as the barge moves forward. Installation associated with coiling and uncoiling is related to the bending moment and strain relationship of the pipeline, A highgrade pipe material is required when the reel-lay method is used. This paper is concerned with the highly plastic bending moment of the pipeline, including the effect of ovality. Moment calculation in the pipe is accomplished by the numerical method, including the variable ovalities during the plastic bending of the pipe string. The new calculation method of the high plastic bending moment was applied to the reel-lay method.

• International Journal of Ocean System Engineering
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• 제2권3호
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• pp.176-184
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• 2012

Installing floating structures in a coastal area requires careful observation of the finite-depth effect. In this paper, a Rankine panel method that includes the finite-depth effect is developed in the time domain. The bottom boundary condition is satisfied by directly distributing Rankine panels on the bottom surface. A stepwise analysis is performed for the radiation diffraction problems and consequently freely-floating motion responses over different water depths. The hydrodynamic properties of two test hulls, a Series 60 and a floating barge, are compared to the results from another computation program for validation purposes. The results for both hulls change remarkably as the water depth becomes shallower. The important features of the results are addressed and the effects of a finite depth are discussed.

• Journal of Advanced Marine Engineering and Technology
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• 제34권3호
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• pp.399-406
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• 2010

The aims of this study are to provide data on the ozone dosage control system and TRO sensor performance, to assess the performance of the degradation of total residual oxidant (TRO) neutralizer and to provide data on degradation rates of TRO in the ballast tanks, following treatment by the Ozone BWTS. This study includes the results of an evaluation of the TRO neutralizer, which was tested on the test barge. Accordingly, it has undertaken the evaluation of TRO degradation rates following treatment by the Ozone BWTS.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2006년도 추계학술발표회
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• pp.91-96
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• 2006

최근 예부선 결합선박에 대한 해양사고가 빈발하고 있다. 어선을 제외한 선박사고 중 36% 로 가장 높은 비율을 차지하고 있으며, 매년 예부선에 의한 해양사고가 증가하고 있다. 예부선에 의한 해양사고는 증가하고 있으나 예부선의 안전 운항 방안에 대한 체계적인 방안 마련이 부족한 실정이다. 본 연구에서는 예부선의 안전운항 방안 중에서 인적요소부분의 문제점을 도출하고 그에 대한 개선방안을 제시하여 예부선에 의한 해양사고를 방지하는데 목적이 있다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2011년도 추계학술대회
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• pp.49-50
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• 2011

예부선 운항 시뮬레이션은, 선박 운항 시뮬레이션의 자선의 동적 거동의 모사 뿐만 아니라 예인줄 및 예인줄에 의해 영향을 받는 부선의 거동을 표현해야 하는 다른 특성을 가지고 있다. 이러한 특성들을 시뮬레이션 가시화에 반영하기 위해 그래픽 렌더링 엔진과 같은 소프트웨어 뿐만 아니라 부선의 상태를 모니터링하기 위한 후방 가시화와 같은 하드웨어 구성을 제안하여 적용하였다. 본 논문에서는 이와 같은 기존의 연구들을 확장하여 예부선 전용의 시뮬레이션 가시화로의 응용에 대해 초점을 맞추고 있으며, 이를 통해 예부선 운항에 적합한 가시화의 구현 내용을 다루고자 한다. 이와 같은 하드웨어와 예부선 전용의 소프트웨어를 통해서 예부선 운항과 관련된 시뮬레이션이 시뮬레이터 사용자에게 직관적인 시뮬레이션 내용을 전달할 수 있을 것으로 기대된다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2017년도 추계학술대회
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• pp.238-240
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• 2017

파랑 중 선수파의 영향을 줄이기 위해 도입된 Axe Bow선형은 파랑 중 항해 시 선수부에 과도한 Spray현상이 발생한다. 이를 억제하고자 선수 부가물이 도입되었으나, 수치해석적 연구가 필요할 것으로 판단하였다. 선수 부가물은 Spray rail에서 착안하였으며, 구현이 쉽고 설계 파라미터를 제시 할 수 있는 Barge형상으로 적용하였다. 본 연구에서는 선수 부가물의 길이 변화에 따른 Axe Bow 선형의 Spray 억제를 수치해석적으로 고찰하였다.

• 대한조선학회논문집
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• 제45권1호
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• pp.63-72
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• 2008

This study considers the motion response of multiple adjacent floating bodies in waves. As a method of solution, a three-dimensional Rankine panel method is adopted in time domain. For the validation of the developed numerical method, the motions of two adjacent Series 60 hulls and ship-barge model are estimated. The computational results are compared with other numerical and experimental analyses, showing favorable agreement.