• 해양환경안전학회지
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• 제28권5호
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• pp.791-799
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• 2022

유선 및 도선 중 선박길이 12미터 미만인 소형선박은 선박안전법에 따른 복원성 기준 적용이 면제되며, 유선 및 도선 사업법에 따라 승객 및 선원이 탑승 가능한 면적을 고려하여 승선정원을 정하고 있다. 이러한 유선 및 도선 중에서는 건조 이후 차양의 설치 등 복원성에 영향을 미치는 상부 구조물을 설치하는 사례도 적지 않다. 이에 본 연구에서는 상부 구조물을 설치한 도선에서 실제 발생한 전복사고의 사례를 바탕으로 해당 도선의 복원성을 추정하여 사고 원인을 분석하고자 하였다. 분석 결과, 승선정원을 초과한 상태에서 승객들이 동시에 하선하고자 기립하여 복원성이 악화된 것으로 나타났으나, 해당 도선이 승선정원을 준수하더라도 한쪽 현의 승객들이 기립하면 횡경사에 의한 전복의 가능성이 존재하였다. 따라서, 보다 안전한 유선 및 도선사업을 위하여 선박길이 12미터 미만의 유선 및 도선에 대하여 건조 및 개조 시 실선 복원성 시험에 의한 승선정원 산출, 승선정원의 총중량 한곗값 제시 등을 개선방안으로 제시하였다.

• 대한조선학회지
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• 제25권1호
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• pp.3-10
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• 1988

This paper presents some experimental investigations on the effectiveness of the Stern-End-Bulb(SEB) and the design procedure of the optimum one. Experimental method was discussed to search the optimum SEB and the resistance reduction rate was investigated from the resistance test results of the SEB series for a passenger boat and a container ship. The contribution of SEB on the propulsive coefficients was discussed from the self-propulsion test results for a container ship. It would be expected that the power saving rate is about 5.8 percents for a passenger boat and 3.6 percents for a container ship by optimum SEB, respectively.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2003년도 춘계학술대회 논문집
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• pp.221-224
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• 2003

This study was carried out to develope a basic form of planning hull type fishing boat. G/T 10ton class is selected as object hull form, and hull form is designed in Chosun University. A series of test results of LCG variations for 5 different LCG points are presented in this paper. The test was performed in Davidson Laboratory, and the scope of tests include resistance, trim and sinkage.

• 수산해양기술연구
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• 제45권4호
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• pp.267-275
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• 2009

According to the recent statistics of marine casualties in Korea, fishing boats are more likely to be ended in the casualties, and small fishing boats especially cause much more accidents in sinking and capsizing than any other big vessels. These casualties were mainly produced from the ignorance on the lack of own ship stability. From this view, this study aims to analyze the characteristics of stability on the crab trap fishing boat receiving transverse wave by means of carrying out the water tank test. The rolling angle of the model ship was affected largely with the displacement and the wave period of it, and the trends were shown that the magnitude of the angle was proportional to the displacement, but inversely to the wave period. And the wave height had effect on the rolling angle just in the specific range of the wave period. The force of steady wind didn't have influence on the rolling variation significantly.

• 대한조선학회논문집
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• 제50권3호
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• pp.153-159
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• 2013

The power transmission system has always been considered critical for a human powered boat(or water bike) since it first showed up at Human Powered Vessel Festival. Mechanical problems, such as abrasions and other damages of the gear system for the power transmission, lead to poor durability and low efficiency of a boat. This paper described mechanical problems and a design process of power transmission system and then suggested the method to solve the problems. It is selected a module and a type of gears that are structurally stable thus can transmit the power durable. Especially the lower gear box is applied to CRP(contra rotating propeller) system for improving the structural stability and the propeller efficiency as well. As the results, the upper and lower gear box are designed and manufactured. And from the trial test, it is confirmed that the power transmission system is reliable.

• International Journal of Naval Architecture and Ocean Engineering
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• 제4권4호
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• pp.488-503
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• 2012

The stern boat deployment system was investigated to evaluate the capability of launching and recovering rigid hull inflatable boat (RHIB) via the stern ramp. The main parameters to launch and recover RHIB were tested at the design stage. The combined hydrodynamic effect of the stern wake and the water jet flow made it difficult to maintain the maneuvering and sea-keeping ability of RHIB approaching to the stern ramp. The safe recovery course was proposed to maintain the directional control of RHIB and to reduce the combined hydrodynamic effect in the transom zone. To evaluate the feasibility of RHIB recovery, the stern sill depth was measured in various conditions and the ramp availability time was obtained. Also, the experimental percent time operability (PTO) test was performed by the number of successive launching and recovering operations.

• 대한조선학회논문집
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• 제45권2호
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• pp.124-131
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• 2008

This paper presents the analysis of resistance performance and bow waves for the resistance-minimized hull form of small fishing boat by using numerical simulations and model tests. The resistance-minimized hull form is developed from an original hull form which is selected from existing small fisher boats in our country. In order to estimate the resistance performance for the original and the developed hull form, several numerical simulations and model tests are carried out. Marker and Cell(MAC) method and Marker-Density method are adopted to simulate the free-surface bow waves around advancing hull surface. The results of numerical simulations are compared with the model tests in towing tank. The results show that the resistance performance of the resistance-minimized hull form is improved than that of the original hull form. The results of this study will be a good guide to the hull form development of small fishing boats in future.

• 한국해양공학회지
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• 제17권5호
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• pp.88-94
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• 2003

A series of tests of 5 model ships, selected from a data survey of 10 Gross Tonnage actual fishing boats, were performed in two circulating water channels (Chosun University in Korea and WJFEL in Japan), in order to develop the basic hull form of a 25 knots-class fishing boat. Resistance tests, trim and sinkage measurements and wave pattern observations etc., were included in each I1wdel test, and the model test results were compared and analyzed. The result was as follows: P-4 hull form ship changed into Deep V type bow is the best hull form with good performance, especially with regard to ship's resistance efficiency.

• 한국해양공학회지
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• 제32권6호
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• pp.518-526
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• 2018

As a new technical approach, this paper introduces a method for improving an electrically propelled outboard motor in consideration of the driving system applied to an electric-propulsion boat with solar cell energy. The most efficient model for a drive shaft, propeller shaft, and bevel gear was suggested and examined with respect to the results of test operation in prototype mode. Furthermore, this research included a performance evaluation of the manufactured prototype to acquire the purposed quantity value and the development items. After manufacturing the desired prototype of an electrically propelled outboard motor, the maximum sail time, thrust force, noise, and weight were evaluated in a performance test. An additional test in relation to the maximum sail speed (knots) of the completed prototype was conducted using a sea trial evaluation to acquire the optimum quantity.

• 한국항해항만학회지
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• 제38권6호
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• pp.585-591
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• 2014

본 논문의 주 목적은 프루드 수가 0.5 이상인 중형 경비정의 속도성능을 모형시험 이전에 CFD 결과를 바탕으로 기존의 모형시험자료를 활용하였다. 모형시험 이전에 CFD를 이용하여 선속 별로 추정된 제동마력이 주어진 엔진마력을 만족하는지를 평가 하였다. 대상선박은 선미가 서로 다른 두 가지 선형을 선정하였다. 점성 유동장 계산은 상용 CFD 코드인 STAR-CCM+를 사용하였으며, 자유수면과 자세 변화(동적 트림)를 모두 고려하였다. 알몸 선체의 저항 값은 CFD를 이용하여 추정되었다. 점성 유동 해석을 통해 두 가지 선형의 자유수면 파형, 압력분포, 한계유선 그리고 프로펠러 면에서의 속도분포를 비교하였다. 점성 유동 해석 결과를 바탕으로 두 가지 선형에 대한 유효마력 즉, 저항성능을 평가하였다. 부가물 부착에 따른 저항 증가량과 준추진효율 계수(ETAD, ${\eta}_D$)는 모형시험 자료를 활용하였다. 중형 경비정과 같은 고속선박에 관한 속도성능 추정법이 CFD와 기존 시험자료를 이용하여 개발되었다.