• International Journal of Naval Architecture and Ocean Engineering
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• 제12권1호
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• pp.178-183
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• 2020

A series of experiments covering lowest three natural frequencies of rolling coupled pitching were conducted to investigate liquid sloshing with low liquid depth. The test results show that the most violent liquid sloshing in rolling and pitching is located in the vicinity of the first order natural frequency (f1). When the excitation frequency of rolling and pitching is located between 0.98f1 and 1.113f1, roof-bursting phenomenon of liquid appeared, and the maximum impact pressure is at 1.09f1. When the external excitation frequency is at 1.113f1, the number of sloshing shocks decreases sharply. Furthermore, the space distribution of the impact pressure on the left bulkhead and the top bulkhead was analyzed. It is concluded that with low liquid filling, the impact load is greater near the free surface and the top of tank, and the impact position of the side bulkhead increases with the increasing of the frequency near the resonant frequency.

• 한국시뮬레이션학회논문지
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• 제18권2호
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• pp.19-27
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• 2009

본 논문은 군항에서의 선석할당문제(BAP)를 다루고 있다. 일반적으로 민간선박이 컨테이너 부두에서 컨테이너 적 하역 작업을 주로 하는 반면에 해군함정은 긴급수리, 무장적재, 유류수급 등 다양한 서비스를 필요로 한다. 또한 해군함정은 제한된 부두의 능력과 설비 때문에 민항에선 거의 일어나지 않는 잦은 선석이동을 해야 한다. 본 연구의 목적은 전시상황 하에서 여러 해군함정이 필요한 서비스를 받기 위해 부두에 입항 시 입항하는 모든 함정이 최단시간 내 요구 서비스를 모두 마치고 다시 전비태세를 유지토록 서비스 완료시간을 최소화하는 것이다. 즉, 부두에 계류중인 함정 수의 최소화를 통하여 해상에서 교전 가능한 함정의 수를 최대화하는 것이다. 제시된 문제를 해결하기 위해 혼합정수계획법(MIP)으로 수리모형을 작성하였고 ILOG CPLEX 11.0을 이용해서 최적해를 산출하였다. 연구결과는 수리모형에 의한 선석할당이 불필요한 선석이동을 최소화하고 전시 교전에 참가할 수 있는 함정 수를 더 증가시킬 수 있다는 결과를 나타낸다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제2권1호
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• pp.34-38
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• 2010

Field investigations have been carried out in two 60-day stages on the surf beat low frequency waves in Anzali port, one of the main commercial ports in Iran, located in southwest coast of the Caspian Sea. The characteristics of significant water waves were measured at three metering stations in the sea, one at the entrance of the port and three in the basin. The measured data were inspected to investigate the surf beat negative effects on the tranquility of the port. Using field measurements and complementary numerical modeling, the response of the basin to the infra-gravity long waves was inspected for a range of wave frequencies. It was concluded that the water surface fluctuations in the port is strongly related to the incident wave period. The long waves with periods of about 45s were recognized as the worst cases for water surfaceperturbation in the port. For wave periods higher than the mentioned range, the order of fluctuation was generally low.

• 통상정보연구
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• 제10권4호
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• pp.301-319
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• 2008

The development of Korea in the Northeast through trade is not a matter of choice as far as national strategy is concerned, but is an important national policy that is a matter of life or death which will determine the future fate of Korea. This thesis will attempt to arrive at a general, tangible plan for the development of Korea in the Northeast centered around trade by examining the change in naval environment at home and abroad, the given economic situation in the Northeast, and the present state of essential port development in Korea-China-Japan. Its objective will be to provide strategies for the development of Busan port confrontation. For the last ten years, China has been growing at a rapid rate. Since a lot of the volume of naval trade is being transferred from Korea to China, we must do everything we can to improve the service and reduce cost. In addition, Japan also is losing international position. Japan's government and the private industry are trying to make Super Core Ports a prominent feature of their port system. If the Busan port system is to remain competitive, these aspects of the Japanese port system must be kept in mind to prevent trade from going to other ports with more competitive systems.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2001년도 Proceeding of KIN-CIN Joint Symposium 2001 on Satellite Navigation/AIS, lntelligence , Computer Based Marine Simulation System and VDR
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• pp.81-87
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• 2001

In this article, we have done some analysis about the collision-avoidance specialty of “pressing complexion” and “pressing danger”in the meet process of two boats, and offered a mathematic model of differential coefficient countermeasure decision for collision-avoidance, which adapt to the right complexion. The basal idea is, in the right condition whatever do the coming boat do, and our boat will always adept dynamic, continuous and the best countermeasure. When both the controlling capabilities of two boats have advantage and inferior position, we can working-out with the qualitative differential coefficient countermeasure.

• 한국항해항만학회지
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• 제37권1호
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• pp.55-61
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• 2013

In this paper, ship accidents are analyzed briefly and the main objective is to investigate a potential technological approach for risk assessment of vessel stability. Ship nonlinear motion equation and main parameters that induce ship capsizing in beam seas have analyzed, the survival probability of a ferry in random status have estimated and finally find out a risk assessment concept for ship's intact stability estimation by safe basin simulation method. Since a few main parameters are considered in the paper, it is expected to be more accurately for estimating ship survival probability when considering ship rolling initial condition and all other impact parameters in the future research.

• 한국항해항만학회지
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• 제29권8호
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• pp.679-684
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• 2005

본 논문에서는 수중운동체의 운동수학모형 정립 및 최적제어 방안 연구를 위해, 수중운동체의 6자유도 운동 방정식을 유도하고, UUV 모형의 사항시험을 통해 6방향의 유체력을 구하였다.

• 한국항해항만학회지
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• 제33권9호
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• pp.629-634
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• 2009

Vessels stability problems need to resolve the nonlinear mathematical models of rolling motion. For nonlinear systems subjected to random excitations, there are very few special cases can obtain the exact solutions. In this paper, the specific differential equations of rolling motion for intact ship considering the restoring and damping moment have researched firstly. Then the partial stochastic linearization method is applied to study the response statistics of nonlinear ship rolling motion in beam seas. The ship rolling nonlinear stochastic differential equation is then solved approximately by keeping the equivalent damping coefficient as a parameter and nonlinear response of the ship is determined in the frequency domain by a linear analysis method finally.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2009년도 추계학술대회
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• pp.239-240
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• 2009

Vessels stability problems need to resolve the nonlinear mathematical models of rolling motion. For nonlinear systems subjected to random excitations, there are very few special cases can obtain the exact solutions. In this paper, the specific differential equations of rolling motion for intact ship considering the restoring and damping moment have researched firstly. Then the partial stochastic linearization method is applied to study the response statistics of nonlinear ship rolling motion in beam seas. The ship rolling nonlinear stochastic differential equation is then solved approximately by keeping the equivalent damping coefficient as a parameter and nonlinear response of the ship is determined in the frequency domain by a linear analysis method finally.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2005년도 추계학술대회 논문집
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• pp.63-68
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• 2005

본 논문에서는 수중운동체의 운동수학모형 정립 및 최적제어 방안 연구를 위해, 수중운동체의 6자유도 운동 방정식을 유도하고, UUV 모형의 사항시험을 통해 6방향의 유체력을 구하였다.