• 수산해양기술연구
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• 제51권1호
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• pp.61-70
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• 2015

In an attempt to improve the maneuvering character of hull form renovated tuna purse seiner. A renovation was carried out on the 3 tuna purse seiner fishing vessel. To grasp the progress of maneuvering and resistance on ship B (730 ton class), new bulbous bow was only attached. The ship A (740 ton class) and C (600 ton class) were modified for new bulbous bow, enlarged slipway and rudder. And then the zigzag and the turning test were carried out. According to the turning test, the advance and the tactical diameter were improved very much for the modified ship. The sea trial was carried out for the original and modified ship A. It is showed that the results of sea trial corresponded with that of the tank test on the whole. In the result of the zigzag test on ship B, the turning ability was improved very much, but the yaw checking ability was deteriorated in just some degree. In the result of the zigzag test on ship C, the turning ability and yaw checking ability were remarkably improved. Ship C was greatly improved among the three ships for the maneuvering character of modified hull form.

• 한국항해항만학회지
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• 제27권6호
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• pp.661-667
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• 2003

There are certain guidelines on the channel design such as domestic guidelines（Korean and japanese, etc.）and international guideline known as PIANC Rules（Permanent International Association of Navigation Congresses Rules）, in the world These rules have considered many factors such as natural conditions, ship maneuverability and geographical features etc. But it is contented toot the area of these rules toot are meant to facilitate the ease of ship-handling is insufficient. To satisfy this point in design process, it is necessary to take into account the difficulties encountered in ship-handling within these inland waterways. Because many vessels are navigating at the same time within these waterways, the specific navigable traffic volume should be considered with regard to the standard process of route designing. It must also be considered with regard to the volume of navigable traffic bemuse of ship-handling difficulty toot arises within the same waterway with varying amounts of traffic volume because toot ship-handling/manueverability is directly influenced by these factors. This paper aims to propose a new approach to the design of standard inland water route considering the traffic volume and the shape of waterway. Also consider the relationship among these factors may affect to the ship-handling difficulties.

• 대한조선학회논문집
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• 제61권1호
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• pp.29-43
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• 2024

The present study concerns a feasibility study for applying principal component analysis to ship dynamics in maneuver. Using the four degrees of freedom standard modular model for ship dynamics maneuver simulations of large angle zigzag tests with rudder deflection angle variations are conducted. The datasets of ship motion, hydrodynamic force, and moment during the maneuver are acquired to identify the principal modes. The covariance matrix of obtained ship dynamics variables shows a strong linear correlation between the motion, hydrodynamic force, and moment, except the surge force. Four eigenvectors of the covariance matrix are selected as the principal modes of ship dynamics. Using the principal modes, ship motion in turning circle and zigzag tests is reconstructed, showing good agreement with the original data.

• 한국항해항만학회지
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• 제43권6호
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• pp.369-376
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• 2019

선박이 제한수로를 운항할 때에는 기존 심수 및 천수 중을 운항하는 선박의 조종특성과 일반적으로 다르기 때문에 선박의 안전한 항해를 위해 달라지는 선박의 조종특성 추정이 중요하다. 본 연구에서는 제한수로를 운항하는 선박의 조종성능을 추정하기 위해 조종운동 방정식과 가상 구속모형시험 시뮬레이션을 통한 유체력 미계수를 이용하여 조종성능을 추정하였다. 조종 수학 모델 중 선체, 프로펠러, 타를 분리하여 유체력을 모델링하는 방식인 모듈형(modular type) 모델에 제한수로의 영향을 고려하는 항을 추가하여 제한수로 중 조종성능을 추정 연구를 수행하였다. 제한수로 중 선체에 작용하는 유체력 미계수를 도출하기 위하여 상용 CFD 프로그램을 이용한 가상 구속모형시험 시뮬레이션을 수행하였다. 최종적으로 제한수로 중 직진 시뮬레이션과 Zig-zag 시뮬레이션을 수행하여 제한수로의 영향이 고려된 조종 시뮬레이션을 수행하였다. 특히 선박의 침로 안정성능을 평가하기 위해 Zig-zag 시험을 수행하는데, 측벽으로 인한 선박 주위의 비대칭 유동이 좌현과 우현에 압력차이를 발생시켜 선박의 궤적에 큰 영향을 미침을 확인하였다.

• 한국항해항만학회지
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• 제43권6호
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• pp.403-412
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• 2019

선박의 조종운동특성은 선종뿐만 아니라 같은 선박이라 할지라도 속도나 흘수에 의해서도 달라진다. 최근에 초대형선박이 크게 증가하고 있어 해양사고 발생 시 막대한 물적, 환경적 피해가 발생할 수 있으며, 이에 따라 선박조종의 중요성은 더욱 커지고 있다. IMO는 STCW 95 개정협약서를 통해서 해기사들이 시뮬레이터를 이용한 교육을 받도록 강제하고 있다. 그러나 Full Mission Ship Handling Simulator(FMSS)는 고가일 뿐만 아니라 사용하는 데에 제한이 많고, PC기반의 시뮬레이터는 서로 다른 사용자가 함께 시뮬레이션을 할 수 없다는 단점이 존재한다. 본 연구는 네트워크를 기반으로 두 사람이 각자의 PC를 이용하여 함께 시뮬레이션을 할 수 있도록 하여 FMSS와 PC기반의 시뮬레이터가 갖는 단점을 해결하고자 Nomoto 응답모델의 해석 및 수치계산과 레이더 기능 구현, 데이터통신 프로토콜 설계, Graphic User Interface(GUI) 구축 등을 통해 네트워크 기반의 시뮬레이터를 구현하였다. 그리고 개발된 시뮬레이터의 유효성을 검증하기 위해 한국선급, IMO의 선박조종성기준에 따라 시뮬레이션 결과와 한국해양대학교 한바다호의 실선시험결과를 비교·분석하였다. 항목별 시험결과를 정리하면 상대오차 범위는 0 ~ 32.1 %, 평균 13.7 % 이었으며, IMO 선박조종성기준을 모두 만족하였다.

• 수산해양기술연구
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• 제32권3호
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• pp.273-285
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• 1996

Generally, the flow around the ship's hull often appear 3-dimensional separation at the bow and stem, and the vortex by this flow affects greatly the resistance propulsive efficiency and maneuverability of the ship. This study is compared the calculated result based on the streamlines calculation method with the experimental result by oil fIlm method to analyze the patterns and characteristics of the flows around the ship's hull of chine form. DTMB Series 62, 4667-1 vessel was selected as a sample ship of chine form and model ship was painted with the mixture of oil-color, paint, and poly wax at the surface of the vessel and tested in the model towing tank of Inha University. The results obtained in this study are listed briefly as follows ; 1. For the single chine form, after $4\frac{1}{2}$ station the streamlines are crossed at the chine line and the streamlines are converted to the vortex follow the chine line. 2. For the single chine form, the vortex appered increases and severely in and arround the stern. 3. The approximate streamlines for the ship's hull of chine form can be assigned by the use of the Watanabe's basic transformation formular.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2018년도 추계학술대회
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• pp.4-6
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• 2018

Traditional methods of research on ship maneuvering performance were estimated in calm water. Ship maneuverability in waves is of vital importance for navigation safety of a ship (ITTC, 2008). The accurate estimation of force and moment acting on the ship and rudder behind propeller are necessary because the rudder, propeller and hull interaction is of key importance. In addition, course-keeping ability and maneuvering performance of a ship can be significantly affected by the presence of wave. In this study, the model test is performed in the regular wave in the square wave tank in Changwon National University and the hydrodynamic force acting on the ship hull and rudder behind the propeller in various wave directions is investigated. The effect of wavelength and wave direction on hydrodynamic force acting on ship and rudder behind propeller in regular waves is discussed.

• 대한조선학회논문집
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• 제61권4호
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• pp.226-235
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• 2024

A method for quantifying the adaptability of ship maneuver scenarios for data-driven modeling of ship dynamics is developed based on the principal component analysis. A random maneuver scenario is suggested as a reference for ship dynamics, which can obtain the converged principal components of ship dynamics features by the Monte Carlo simulation. Principal components of conventional maneuver scenarios defined by the International Maritime Organization (IMO) are compared to that of the random maneuver. A conventional ship dynamics model for a container carrier vessel for four degrees of freedom dynamics is introduced to simulate the random and IMO maneuver scenarios. It is confirmed that the IMO tests follow the tendency of random maneuver scenario in terms of execution time and adaptability.

• 대한조선학회논문집
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• 제41권5호
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• pp.28-33
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• 2004

Generally Horn-type rudders have been used for single propeller and single rudder system. The reason is that the rudder torques of Horn-type rudder are smaller than those of Spade rudder with same lift force. But it is found that the rudder cavitation occurs on a Horn-type rudder of fast container ship. In this paper the comparison results of Horn-type and Spade rudders are described. HPMM tests are carried out to compare the effects of two rudder types on the maneuverability of a ship. It is shown that the maneuvering performance of a ship equipped with Horn-type rudder is better than that equipped with Spade rudder by comparing the test results and maneuvering coefficients at scantling condition. The reason is that the movable part area of Horn-type rudder is about 14％ larger than that of Spade rudder with same total area. And the rudder torque of Spade rudder is greater than that of Horn rudder. At ballast condition, however, the effect of rudder type is negligible.

• 수산해양기술연구
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• 제56권3호
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• pp.238-245
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• 2020

In this study, a motion control problem for the vessel towed by towing ship on the sea is considered. The towed vessel does not have self-control capabilities such that its course stability totally depends on the towing ship. Especially, in the narrow canal, river and congested harbor area, extreme tension is required during the towing operation. The authors, therefore, propose a new control system design method in which the rudder is activated to provide its maneuverability. Based on the leader following system configuration, a nonlinear mathematical model is derived and a backstepping control is designed. By experiment results with nonlinear control framework, the usefulness and effectiveness of the proposed strategy are presented.