• 한국항해항만학회지
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• 제33권4호
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• pp.255-261
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• 2009

Prediction of the stability for ships is very complex in reality. In this paper, risk based approach is applied to predict the probability of capsize for a certified ship, which is effected by the forces of sea especially the wave loading Safety assessment and risk analysis process are also applied for the probabilistic prediction of stability for ships. The probability of shipsencountering different waves at sea is calculated by the existed statistics data and risk based models. Finally, ship capsizing probability is calculated according to single degree of freedom(SDF) rolling differential equation and basin erosion theory of nonlinear dynamics. Calculation results show that the survival probabilities of ship excited by the forces of the seas, especially in the beam seas status, can be predicted by the risk based method.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2014년도 추계학술대회
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• pp.245-246
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• 2014

This paper suggests the navigation information display system which is based on augmented reality technology and especially focuses on image analysis technology. Navigator has to always confirm the information from marine electronic navigation devices and then they compare with the view of outside targets of the windows. During this 'head down' posture, they feel uncomfortable and sometimes it cause near-accidents such as collision or missing objects, because he or she cannot keep an eye on the front view of windows. Augmented reality can display both of information of virtual and real in a single display. Therefore we tried to adapt the AR technology to help navigators and have been studied and developed image pre-processing module as a previous research already. To analysis the outside view of the bridge window, we have extracted navigational information from the camera image by using image processing. This paper mainly describes about recognizing ship feature by haar-like feature and filtering region of interest area by AIS data, which are to improve accuracy of the image analysis.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2018년도 추계학술대회
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• pp.341-342
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• 2018

대양을 운행하는 선박의 최적 항로에 대한 기존의 연구와는 다르게, 본 연구에서는 연안을 운행하는 선박의 항로 계획을 위한 최적화 방법을 제안하였다. 일반적으로 연안을 운행하는 여객선의 경우 허가 받은 항로를 기준으로 항로에 표시된 변침점을 따라 운행한다. 따라서 본 연구에서는 변침점 사이의 속도를 결정하기 위한 제동 동력과 시간을 고려한 목적 함수를 제안하였고, 목포와 제주를 오가는 여객선의 실제 항로에 본 연구에서 제안한 방법을 적용하여 최적의 속도를 결정하였다.

• 시스템엔지니어링학술지
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• 제16권2호
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• pp.110-117
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• 2020

In this paper, we estimated the straight line stability by performing a 3 degree of freedom spiral test simulation of a intact/damaged surface combatant using the hydrodynamic coefficient obtained through the PMM(Planar motion mechanism) test based on system engineering process. A model ship was ONR Tumblehome and damaged compartment was set on the starboard bow. As a result of conducting a spiral test simulation based on the experimental results of J.Ha (2018), the asymmetric straight line stability due to the damaged compartment was confirmed. In the case of a ship in which the starboard bow was damaged, it was confirmed that it had the characteristic to deflect to the left when going straight. Also, when estimating the straight line stability of a both port and starboard asymmetric surface combatant, a separated equation of motion model that sees the port and starboard as different ships seems suitable.

• 한국항해항만학회지
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• 제36권10호
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• pp.819-824
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• 2012

본 논문에서는 국제협약인 STCW(International Convention on Standards of Training, Certification and Watchkeeping for Seafarers)에 명시된 항해당직을 담당하는 해기사의 자격증명에 관한 강제적 최저요건을 분석하고, 해군 초급장교들의 해기능력과 관계되는 전반적인 교육과정 및 평가 시스템을 비교 분석하였다. 그 결과, 해군사관생도 출신의 초급장교는 교육과정 및 내용, 엄격한 기숙생활, 단계별 체계적인 함정실습체계, 함정근무 장교 능력평가제도 등 모든 내용이 STCW 협약에 근거하여 부족함이 없다고 판단된다. 그리고 일반대학을 졸업한 사관후보생 및 학군사관후보생 출신의 초급장교는 교육과정이 STCW 협약에는 다소 부족하지만 항해안전을 위한 기초능력은 배양되었다고 판단된다.

• 한국항해항만학회지
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• 제29권8호
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• pp.685-692
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• 2005

본 연구에서는 첨단화되어 가는 GPS 수신기 환경 하에서도 재래항법에 비해 그 활용도가 저조한 해군함정에서의 GPS 수신기 활용 현황을 알아보고, 해군함정에 설치된 GPS 수신기의 정밀도를 조사 및 분석하였다. 또한, 해군함정 근무자들에 대한 면담 및 설문 조사를 통하여 사용자가 갖는 GPS 수신기에 대한 신뢰도와 활용도를 알아보았고, 해군차원에서의 GPS 수신기 시스템의 발전방안을 제시하였다. 본 연구의 결과는 다음과 같다. 해군함정 근무자들은 GPS 수신기의 정밀도를 지문항법에 의한 실측위치 수준으로 인식하고 있으나 활용도는 실측위치나 R/D위치의 산출이 불가한 경우 또는 이 위치들과의 비교 및 확인용도 정도로만 사용하고 있음을 알 수 있었다. 해군차원에서 GPS 수신기 시스템의 발전방안으로는 고장이 잘 나지 않고 전자해도와 연동된 GPS 수신기 시스템의 도입 및 병렬시스템 설계 등을 제시하였다.

• 해양환경안전학회지
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• 제28권5호
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• pp.819-826
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• 2022

스마트 항만시스템을 구축하기 위해서는 무엇보다 선박을 자동으로 계류시킬 수 있는 시스템이 요구된다. 항만의 자동계류시스템의 허용 계류력을 산정하기 위해서는 선박의 특성을 고려하고, 해양환경적 외란으로 부터 발생된 외력을 정확히 계산해야 한다. 이러한 환경적 외란의 크기를 정확히 추정하는 것은 자동계류장치 설계를 위해서 매우 중요한 요소이다. 본 연구에서는 항만 및 어항 설계기준에 따라 한바다호에 대한 계류력을 추정하였다. 그 결과 한바다호에 작용하는 대부분의 외력은 바람으로부터 기인되는 것을 확인하였다. 가장 극한 해양조건(B.F 6)에서 한바다호에 작용하는 종방향 힘은 18kN, 횡방향 힘은 248kN으로 나타났다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제10권3호
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• pp.235-249
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• 2018

The Artificial Neural Network (ANN) model has been known as one of the most effective theories for automatic ship berthing, as it has learning ability and mimics the actions of the human brain when performing the stages of ship berthing. However, existing ANN controllers can only bring a ship into a berth in a certain port, where the inputs of the ANN are the same as those of the teaching data. This means that those ANN controllers must be retrained when the ship arrives to a new port, which is time-consuming and costly. In this research, by using the head-up coordinate system, which includes the relative bearing and distance from the ship to the berth, a novel ANN controller is proposed to automatically control the ship into the berth in different ports without retraining the ANN structure. Numerical simulations were performed to verify the effectiveness of the proposed controller. First, teaching data were created in the original port to train the neural network; then, the controller was tested for automatic berthing in other ports, where the initial conditions of the inputs in the head-up coordinate system were similar to those of the teaching data in the original port. The results showed that the proposed controller has good performance for ship berthing in ports.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 Asia Navigation Conference
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• pp.230-239
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• 2006

The depth, width and alignment of fairway that are main port water facilities should be designed considering the various elements including particulars of design ships, weather and sea conditions around fairway and method of ship-handling. However not only the existing Japanese design standard for fairway and also those of other countries do not take into consideration of such kind of elements and no design standard is made by quantitative analysis. In this circumstance the new design standard (Approach Channels, A Guide for Design) depending on classified various elements and quantitative analysis was proposed in 1997 by PIANC and IAPH. But it was proved that calculated values according to this standard were unfounded and had some problems to output the discontinuous value by small difference of calculation condition because the each value fur each element was simply added. And also it is hard to apply this standard to the design of port water facilities in Japan because this [A Guide for Design] is the design standard for long channels in European port. The proposal of more reasonable Japanese standard will be expected by applying the study result of naval architecture and navigation and by the cooperation of ship operators to use fairway, naval architects to built ships and civil engineers to dredge fairway. The concept of a fairway in 'Design standard fur fairway in next generation' is defined as passage for approach channel) and traffic lane designated by light buoys as navigable water for safe navigation. In 'Design standard for fairway in next generation' depth, width and alignment are picked up among many design elements of a fairway. Design method for those elements is shown based on design ships and navigational environments. This standard shows the method of design for each dimension depending on characteristic on design ship and weather and sea condition. On the other hand, in case of existing fairway, it is possible to decide the size of ship and navigation criteria by opposite analysis.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 춘계종합학술대회 A
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• pp.117-120
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• 2008

본 논문은 차량 충돌방지 레이더의 허상방지용 전파흡수체를 유전손실재료인 $TiO_2$을 이용하여 개발하였다. 먼저 전파흡수체 샘플을 유전손실재료인 $TiO_2$ 와 바인더인 CPE를 사용하여 조성비별 제작하고, 네트워크 아날라이저를 이용하여 측정한 5-parameter로부터 1-Port Method를 이용하여 복소비유전율을 계산하였다. 그리고 계산된 복소비유전율을 이용하여 전파흡수체를 설계 및 제작한 결과 조성비 $TiO_2$:CPE=70:30 wt.%, 두께 1.85 mm, 주파수 76-77 GHz에서 20 dB 이상의 전파를 흡수하는 전파흡수체를 개발하였다.