• Proceedings of the Korea Technology Innovation Society Conference
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• 2013.10a
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• pp.136-152
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• 2013

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.04a
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• pp.227-232
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• 2000

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2010.10a
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• pp.38-39
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• 2010

최근들어 항만건설 및 선박블록 운송의 증가로 대형 부선을 예인하는 예부선과 침몰 선박 인양 및 해상교량공사 등을 위한 해상크레인 운송선단의 통항이 매년 증가 추세에 있다. 우리나라에서 이들 선박의 주 항로는 남해와 서해 연안으로, 이 지역은 도서가 산재해 있고 협수로가 많은 지형적 특성과 연안으로 근접하여 항해 시 강한 조류의 영향을 받으며, 또한 어망과 조업중인 어선들과 많이 조우하게 된다. 특히, 돌발적인 해양 기상적 특징을 포함하고 있다. 이러한 영향에 따라서 이 해역을 통항하는 예부선 및 해상크레인 선단의 조종성능이 크게 저하되어 해양사고의 위험성이 고조되고 있다. 이에 따라서, 이 연구에서는 해상크레인의 연안해역 예항시 안전하게 항해할 수 있는 적절한 조종 방법을 고찰하여 안전운항에 기여하고자 한다.

• Journal of Ocean Engineering and Technology
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• v.5 no.2
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• pp.76-84
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• 1991

본 연구는 피로수명 평가를 위한 새로운 파괴역학적 parameter의 확립에 관한 연구이다. 실질적으로 피로파괴가 일어나는 피로 균열선단의 국소영역에서 변형분포를 미소원형격자측정법을 이용하여 실험적으로 명확히 밝혀내었다. 그리고 이 결과를 기초로 하여 국소피로 변형율장을 대표할 수 있는 피로변형율 확대계수 $\Delta$A를 제안하였다. 또한 새로운 parameter $\Delta$A의 유효성을 여러 피로조건에서 검토한 결과, 균열선단 국소 영역에서 피로 변형율 확대계수 $\Delta$A에 의하여 피로 균열전파 속도평가를 일의적으로 나타낼 수 있음을 확인하였다.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.19 no.1
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• pp.40-45
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• 1983

The paper describes an experimental investigation of axisymmetric diesel spray and flame which is held in rapid compression machine (RCM) with electromagnetic single injection nozzle. The axisymmetric diesel spray and flame are taken with high speed photograph and analysis it with image processor. The data presented include fuel concentration of spray, flame temperature, soot concentration of flame in axial and radial direction at a moment and compared it with each other.

• Journal of Ocean Engineering and Technology
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• v.16 no.6
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• pp.76-81
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• 2002

The purpose of this study is to set up the optimum economical formation of the purse seiner fishing system. For this task, the characteristics of existing purse-seiner fishing system were reviewed, and the possible formations of the fleet in tile purse-seiner fishing system were examined through the reallocation of function for each individual vessel. In addition, economic evaluations of the possible formations of the fleet are carried out. Consequently, it was found that 2-vessel formations have the most economic efficiency. Then, a conceptual system design for the main vessel in the 2-vessel formations was performed. As a result, this paper can be used as a helpful guideline to develop the most profitable and economical fishing system in the fleet type fishery.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.6
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• pp.531-552
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• 2020

In the previous study, both the wave characteristics at the tip of composite breakwater and on caisson were investigated by applying olaFlow numerical model of three-dimensional regular waves. In this paper, the same numerical model and layout/shape of composite breakwater as applied the previous study under the action of one directional irregular waves were used to analyze two and three-dimensional spatial change of wave force including the impulsive breaking wave pressure applied to trunk of breakwater, the effect of rear region, and the occurrence of diffracted waves at the tip of caisson located on the high crested rubble mound. In addition, the frequency spectrum, mean significant wave height, mean horizontal velocity, and mean turbulent kinetic energy through the numerical analysis were studied. In conclusion, the larger wave pressure occurs at the front wall of caisson around the still water level than the original design conditions when it generates the shock-crushing wave pressure in three-dimensional analysis condition. Which was not occurred by two-dimensional analysis. Furthermore, it was confirmed that the wave pressure distribution at the caisson changes along the length of breakwater when the same significant incident wave was applied to the caisson. Although there is difference in magnitude, but its variation shows the similar tendency with the case of previous study.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.4
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• pp.421-427
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• 2015

This study aims at reviewing first the cases of marine accidents of small fishing vessels and vessels towing and being towed and, the problems concerning such lights and shapes that could be misunderstood for those in concerned Rules, or that could impair their distinctive characteristics or obstruct to keep a proper look-out. And then I wish to make a suggestion of the necessity of amending the National Laws which stipulate the rules for the ship's lights and shapes as follows; Firstly, by amending the "Standard of Construction and Equipment for the Less Than 10 Gross Tonnage of Small Fishing Vessels" small fishing vessel must be equipped with the lights and shapes that are the same as those of "vessel engaged in fishing" prescribed by Rule 26 of the "COLREG 1972" and Rule 84 of the "Maritime Safety Law Act". Secondly, "Standard of Fishing Vessels Equipment" which stipulate the rules concerning the exception of the running lights and radar reflector for the small fishing vessels must be amended to meet the requirement of Rule 20 of the "Maritime Safety Act". Thirdly, the definition of "Length of the tow" which prescribed by Rule 2 of the "Maritime Safety Act" must be amended to meet the Rule 24 of the "COLREG 1972". And also I wish to adhere to the importance of displaying the adequate vessel lights and shapes by every mariner for preventing marine accidents.

• Journal of Ocean Engineering and Technology
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• v.6 no.2
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• pp.71-75
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• 1992

기구나 구조물의 피로수명은 노치에서의 피로균열 방생수명에 의하여 지배되기때문에 노치로 인한 피로강도감소계수 $K_f$는 피로설계상 대단히 중요한 인자이다. 노치 선단(Notch root)에서의 피로균열발생명수 N$_c$를 기준으로하면 탄성응력집중계수 $K_t$가 10 정도까지 $K_f$와 $K_t$간에는 거의 직선적인 관계가 있음이 이다- 고에 의하여 명석해졌으나 이는 인장,압축의 축력이 작용하였을 때이며 따라서 기구나 구조부재는 축력외에도 굽힘 피로 하중이 작용하였을때도 많으므로 본 연구에서는 굽힘 피로 하중을 받았을때도 있다. -고의 결론이 적용되는지는 검시코져 본 연구를 실시하였다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.27-28
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• 2002

우리나라의 선망어업은 주변 어장 환경의 변화와 남획으로 인한 어획 자원의 고갈은 물론 통(統)당80명이나 필요한 조업인력 및 과다한 조업경비 절감의 문제로 시급하게 구조개선 방안이 요구되면서 선단조업 형태에서 단선 조업의 형태로 전환을 시도해야 하는 시점에 이르렀고, 이에 알맞은 선망어구 설계 및 어로방법 개선이 시급한 실정이다. (중략)