• 한국해양공학회지
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• 제24권2호
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• pp.41-46
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• 2010

This paper deals with the problem of developing a new decision procedure for the freeboard of a coastal chemical tanker going on the coast. The decision procedure is mainly constructed with the algorithm of estimating statistically the time period that deck wetness will last on the deck of the ship. Deck wetness is one of the most important safety factors for sailing of a coaster. It generally means the situation in which the amplitude of the relative motion between the deck and the surface of the wave exceeds the freeboard. Therefore, in this paper, we proposed that the time during which the amplitude remains above the level of the freeboard should be appraised on the basis of statistical theory. A series of numerical calculations were executed for four different coastal chemical tankers (199G/T Type II, III & 499G/T Type II, III). It was demonstrated that the present decision procedure of freeboard is practical for planning the type of coaster sailing in the sea.

• 한국해안·해양공학회논문집
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• 제28권1호
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• pp.27-33
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• 2016

불규칙 파랑 중에서 직접 예인하는 케이슨의 상판침수에 대한 수치해석을 수행하였다. 패널법을 이용하여 주파수 영역에서의 선형 운동해석을 수행하였고, 통계적 방법을 통해 상판침수를 예측하였다. 시간영역 해석에서는 예인시스템, 환경하중 등을 상세히 구현하여 운동해석을 수행하였고, 상판침수 결과를 주파수 영역에서의 결과와 비교하였다. 또한, 시간 영역 해석에서는 예인선의 수 및 배치에 대한 검토를 수행하여 상판침수 측면에서 예인시스템이 미치는 영향과 운송조건을 고찰하였다.

• 한국환경과학회지
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• 제28권12호
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• pp.1171-1181
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• 2019

Plans to utilize the resources of the coast guard are underway for the revitalization of the area and the development of tourism resources in recent years. As most of the plans have been focused on some specific factors such as geographical or regional conditions, and therefore systematic approaches are needed in corporation with other related projects. This study suggested the measures on activating the coastal tourism resources for Woodoo~Woocheon village in Goheung-gun by using the coastal landscape elements. The current status of natural environment and tourism resources for coastal regions were investigated in Woodoo~Woocheon village and plans for enhancing connectivity with local residents were suggested. Based on the scenic values of coastal region, landscape were assessed from the perspective of the sustainable coastal tourism resources in the future. Several solutions were suggested to enhance tour values; coastal deck road to enhance connectivity between resources and accessibility of foreign tourists, social communication among local residents and authorities, continuous development of cultural and historic resources in local area. In addition, information signs and new stair ways would be needed to improve the accessibility of tourists. In the future, if the plan for this study was to generate profitability with persistence, it suggested that there was a way to move forward in conjunction with the profit rate local projects distributed around it.

• 수산해양기술연구
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• 제49권3호
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• pp.311-326
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• 2013

For providing a basic data concerning with a fishing deck layout design of a trawler the authors conducted the video observations about the working activities of crews on the deck in the different layout of two Korean coastal large stern trawlers (gross tonnage: 139). The winch of the trawler-A was installed on the aft of the fishing deck and the trawler-B, on the forward of the fishing deck. The work and activities of the deck hands on both trawlers were observed using the CCD (charge coupled device) camera installed on each trawler's deck for one month from August 3, 2010. The video data was analyzed by the hierarchical task analysis (HTA) method. In results, numbers of tasks to require deck hands during the hauling net and the casting net were 25 and 28 for the trawler-A and 27 and 48 for the trawler-B, respectively. The working processes were represented a same in both of the trawlers. Location for controlling the deck machineries, the location installed trawl winch, kinds of deck machineries, crew's custom for using deck machineries were the factor affecting to the number of the task. In the case of the improvement suggested in the results is carried out, the reduction percentages of the number of task in the trawler-A and trawler-B were estimated as 24.5% and 51.3%, respectively. Through this study it was found that the quantitative analysis is possible for the work processes, work methods and the work contents in the trawler. Also the suggestion for improving the fishing deck layout design of the trawler was possible by finding out the factors increasing the number of tasks and removing the tasks. We expect that the results of this paper are used as a basic data for designing the layout of deck machineries in the trawler in the future.

• Ocean Systems Engineering
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• 제12권3호
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• pp.285-300
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• 2022

This paper adopts the Smoothed Particle Hydrodynamics (SPH) open-source code SPHinXsys to study the solitary wave interaction with coastal structures. The convergence properties of the model in terms of particle size and smoothing length are tested based on the example of solitary wave propagation in a flat-bottom wave flume. After that, the solitary wave interactions with a suspended submerged flat plate and deck with girders are studied. The wave profile and velocity field near the surface of the structures, as well as the wave forces exerted onto the structures are analyzed.

• 수산해양기술연구
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• 제54권4호
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• pp.324-332
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• 2018

We conducted a questionnaire survey to analyze the current status of the coastal composite fisheries, as well as the improvement point in designing a new type coastal composite fishing boat suitable for Korean fishing environments from April to August 2017. The questionnaire composed of 20 questions about the features of the coastal composite fishing boat and fishing work. The survey sites were selected to cover all parts of the country by considering the geographical position. The significance testing for the response results was accessed by ${\chi}^2$ test and ANOVA. The results revealed that more than half (59.1%) of the fishermen operated one day per voyage and operating alone topped with 22.5% in the number of crews, followed by 2 persons (20.3%) and 5 persons (22.1%). The navigation devices had a high rate of installation and GPS plotter ranked first in the devices. In addition, fish finder ranked first in fishing equipment, followed by net hauler. The most inconvenient work that they felt during the fishing operation was fish handing at 49.8% and other general fishing works like setting and hauling line, deck cleaning accounted for about 25%. The hardest work was the accident by ropes wrapped around propeller and the engine trouble came in second. The most inconvenient facilities to the present design of fishing boat was wheelhouse (76.7%), followed by fish hold (38.5%), and deck (35.1%). Furthermore, inconvenient points related to the movement of fishing gear, noise and vibration of engine, slippery deck and small fish hold exceeded 50%.

• Steel and Composite Structures
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• 제9권5호
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• pp.445-455
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• 2009

This study proposes a system identification technique for a fiber-reinforced polymer deck with neural networks. Neural networks are trained for system identification and the identified structure gives training data in return. This process is repeated until the identified parameters converge. Hence, the proposed algorithm is called an iterative neural network scheme. The proposed algorithm also relies on recent developments in the experimental design of the response surface method. The proposed strategy is verified with known systems and applied to a fiber-reinforced polymer bridge deck with experimental data.

• 한국해안·해양공학회논문집
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• 제30권1호
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• pp.10-18
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• 2018

최근 항만도시가 점점 바다 주변으로 확장되고 관광 및 친수를 목적으로 많은 시설물들이 호안 인근에 건설되기 시작하였다. 이로 인해 태풍 및 폭풍 등이 발생하였을 경우 월파에 의하여 건축물 및 인명의 피해가 직접적으로 발생하고 있다. 이러한 재해로서 재산 및 인명을 보호하기 위하여 많은 방벽구조물이 제시되었으나 주변 경관을 보다 중시하는 최근 경향으로 인해 활발히 적용되지 못하고 있다. 본 연구에서는 월파를 방어할 수 있는 호안 설치형 가동식 방벽에 대하여 제시하였다. 이 가동식 방벽은 상시에는 호안에 설치되어 관광형 데크로 활용되다가 이상 시 기립하여 월파를 막는 기능을 가지고 있다. 본 연구에서는 새롭게 제시된 가동식 방벽 기술의 수리성능, 구조성능을 수치해석을 통하여 검토하였으며, 수리 및 구조적인 측면에서 우수한 성능을 가지고 있는 것으로 분석되었으나 모형실험 등을 통한 후속연구가 필요하다.

• 수산해양기술연구
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• 제56권2호
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• pp.126-137
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• 2020

This study collected and analyzed the fishing process of existing fishing boat and newly built fishing boat by using the video observation methods to understand the improvement of fishing operation efficiency and safety according to the scale change of coastal composite fishing boat. The fishing operation efficiency was calculated by analyzing the frequency of movement, the movement distance and the moving time per basket used in the fishing process to derive the improvement of the newly built fishing boat compared to the existing fishing boat. It was confirmed that the mean frequency of movements decreased to 13.9%, the average moving time decreased to 21.8%, the mean movement distance increased to 20.5% and the movement through the top of gunwale did not occur. Movement of frequency, increased and time according to the fishing operation were directly affected by the width of side passages and the presence or absence of walking obstruction such as bulwark stay, hatch coaming and fishing gears on deck. The results of this study are expected to be used as basic data for redesigning into a safe and efficient coastal composite fishing boat in the future.

• 대한조선학회논문집
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• 제58권1호
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• pp.32-39
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• 2021

Korean coastal fishery suffers from profitability degradation due to a decrease in fisheries resources, pollution in coastal waters, fuel coast increase, and market opening for aquaculture products. The next generation Korean fishing vessel aims at the improvement of energy efficiency, enhancement of crew welfare, and safety. These purposes can be accomplished by adopting a new standard hull form with improved resistance performance and a modernized residence facility on the deck. In order to improve resistance performance, this study attempts to optimize design variables for stern flaps for three kinds of fishing vessels - coastal multi-purpose, coastal trap, and dredged nets. A series of model tests for these fishing vessels was carried out in the towing tank of Pusan National University. The results indicate that for some cases, the stern flap caused the stern trim of the vessel to decrease, leading to the resistance reduction.