• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1992.08a
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• pp.28-28
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• 1992

우리 나라 주요항만의 해면 부진동 현상은 일반적인 파랑 보다 주기가 긴 수분 - 수십분의 주기를 갖는 항만고유의 자유진동으로서 폭풍해일 또는 지진 해일과 밀접한 관계가 있으며 장주기파의 Energy 가 항만내에 크게 영향을 미치는 것을 고려 할때 항만건설, 유지를 위한 설계, 선박의 계류, 묘박지의 정온도, 해난사고 및 화재 방지상 대단히 중요시 되어야 할 요소이다.(중략)

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.2
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• pp.157-162
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• 2018

The increase of risk in port due to the increase in ship size and sea level rises, the standard crown height will increase. In this study, cruise and container ships will need to raise their crown height due to the projected wind pressure areas becoming larger due to the ships' size increase. The mooring assessment was evaluated with the rise of the crown height. The cruise ship of GT 100,000 tons exceeded the permissible breaking force of the mooring line under the crown height conditions of wind speed of 30 kts when the wind direction was $45^{\circ}$ to the direction of the bow. Also, the elevation angle of the pier and mooring line was analyzed and exceeded the crown height, and it was determined that it is necessary to adjust the crown height. Container ships of DWT 100,000 tons were analyzed to exceed the limit of sway motion at the crown height and it was determined that they need to be adjusted to the minimum crown height standard.

• Journal of Navigation and Port Research
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• v.30 no.6 s.112
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• pp.533-539
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• 2006

Today the harbor oscillation problems are the most significant factor to design harbors serving the very large ships. Large vessels moored in the elastic hawsers at the coastal harbors are often displaced due to the resonance between the long period waves and mooring system. The cargo handling may be interrupted and the hawsers may be broken, especially when the amplification becomes remarkable. The most significant harbor which is confronted with harbor oscillation problem in Korea is the Pohang New Port. Many cases of problems are being notified by the pilot association and local office of MOMAF. However, it is difficult to prevent the arrival of long waves musing oscillation within this harbor. Moreover, government already started new port plan at the mouth of Yeongil Bay without treating problems occurred in the Pohang New Port. This study deals with the variation of harbor oscillation due to the construction of 4.1km breakwater at the bay mouth and new port plan. Numerical method used are fairly standard form from the extended mild slope equation The obtained numerical results were compared with the field measurement from the previous study and this will bring a certain level of discussion and consideration of variation in the future port development.

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.1
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• pp.45-54
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• 2008

"Summer Deadweight Tonnage(SDWT)" is used as the criteria of the berthing capacity when establishing port entry limits under current guideline. The important factors affecting to the maximum ship size of possible berthing are mass, length and breath of the ship rather than deadweight. Therefore this guideline should be modified to ensure safety and efficient operation of berth. This study aimed to propose a rational guideline to adjust the berthing capacity. In order to decide proper berthing capacity, three berths of Port of Ulsan were selected and systematic evaluations for the safety of passage transit, berthing maneuvers, ship motions at berth and stabilities of structures were conducted. Small changes of ship size had little effect on those characteristics and little significant differences were found according to the increase of ship size at the same displacement. The evaluation results of the increasement of 50% of berthing capacity at 20,000 DWT, 25% at 40,000 DWT and 13% at 150,000 DWT were within the design criteria in which the berths were built. Therefore, if the channel width, diameter of turning circle, berth length and mooring arrangements are satisfied with the criteria, the current berth limitations should be adjusted by the displacement. as substitute for the deadweight.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2006.06b
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• pp.199-206
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• 2006

Today the harbor oscillation problems are the most significant factor to design harbors serving the very large ships. Large vessels moored in the elastic hawsers at the coastal harbors are often displaced due to the resonance between the long period waves and mooring system. The cargo handling may be interrupted and the hawsers may be broken, especially when the amplification becomes remarkable. The most significant harbor which is confronted with harbor oscillation problem in Korea is the Pohang New Port. Many cases of problems are being notified by the pilot association and local office of MOMAF. However, it is difficult to prevent the arrival of long waves causing oscillation within this harbor. Moreover, Government already started new port plan at the mouth of YoungIl Bay without treating problems occurred in the Pohang New Port. This study deals with the variation of harbor oscillation due to the construction of 4.1km breakwater at the bay mouth and new port plan. Numerical method used are fairly standard form from the extended mild slope equation. The obtained numerical results were compared with the field measurement from the previous study and this will bring a certain level of discussion and consideration of variation in the future port development.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2002.08a
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• pp.35-41
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• 2002

천해역에서 관찰되는 장주기파는 발생 기구에 따라서 surf beat, setdown wave, locked wave, 또는 Far-infra-gravity wave 등으로 다양하게 불리 우며, 모두 0.5-수 분대의 주기를 갖는다. 이들은 정의에 따라 약간씩 다르기는 하지만 모두 계류된 선박의 동요뿐만 아니라 해안선 침식과도 밀접한 관련이 있다는 것이 일반적으로 인정되고있다(가등 등, 1989). (중략)

• Proceedings of KOSOMES biannual meeting
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• 2017.11a
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• pp.104-105
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• 2017

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.4
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• pp.501-509
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• 2010

A floating crane is a crane-mounted ship and is used to assemble or to transport heavy blocks in shipyards. In this paper, the static and dynamic response of a floating crane and a heavy block that are connected using elastic booms and wire ropes are described. The static and dynamic equations of surge, pitch, and heave for the system are derived on the basis of flexible multibody system dynamics. The equations of motion are fully coupled and highly nonlinear since they involve nonlinear mass matrices, elastic stiffness matrices, quadratic velocity vectors, and generalized external forces. A floating frame of reference and nodal coordinates are employed to model the boom as a flexible body. The nonlinear hydrostatic force, linear hydrodynamic force, wire-rope force, and mooring force are considered as the external forces. For numerical analysis, the Hilber-Hughes-Taylor method for implicit integration is used. The dynamic responses of the cargo are analyzed with respect to the results obtained by static and numerical analyses.

• Journal of Ocean Engineering and Technology
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• v.14 no.4
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• pp.17-22
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• 2000

As the offshore oil fields are moved to the deep ocean, the oil production system of FPSO(Floating Production Storage and Offloading System) Type are constructed frequently these days. So, it is very important to estimate the drift motion and damping effects due to the drift motion simultaneously. The components of slow drift motion damping consist of viscous, wave radiation effect and wave drift damping. It is needed to estimate the wave drift damping more accurately than others. The wave drift damping signifies the time-rate of mean wave drift force on oscillating ship or ocean structure which constant speed. In order to calculate this, the 3-Dimensional panel method is employed with the translating and pulsating Green function in the frequency domain. The calculation is carried out for a Series 60 ($C_B$/=0.7) and the results are compared with other numerical ones.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.57-62
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• 2006

Busan New Port, under construction aiming for the hub of Northeast Asia and Partly in operation, had damaged up to 48 billion Won due to Typhoon 'maemi' in 2003. The present criteria of domestic harbor design only describes about the critical wave height with respect to the size of vessel for harbor tranquility. The berth operation ratio which represents the annual available berthing days is depending on the efficiency of cargo handling work and this depends on the motion of the moored vessel due to the wave action and the characteristics of cargo gears. The motion of moored vessel might be related not only to the wave height but also to wave period. Furthermore, the berth operation ratio relies on external forces such as currents and winds, including the characteristics of mooring system and the specification of the moored vessel. In this study we only deal with berth operation ratio in normal sea state, considering wave and current by measured data and numerical calculation. Especially we tried to evaluate the berth operation ratio for each berth adopting the variation of dredging and reclamation plan and the change of wave environment during the process of the new port construction. For better understanding and analysis of wave transformation process, we applied the steady state spectral wave model and extended mild-slope wave model to the related site. This study summarizes comparisons of harbor responses predicted by two numerical predictions obtained at Busan New port site. Field and numerical model analysis was conducted for the original port plan and the final corrected plan.