• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.66.1-66
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• 2001

As choosing proper length of boom of container crane according as sort of vessels(18, 22, 24 columns and so on), reinforcing of capacity of DC motor to transport heavy loads, it´s structure being oversized with flexibility and durability, the study is progressing on the automation for convenient operation and effective control. We often cannot but work slowly caused by swaying(pitching, rolling) of vessel. We can get productivity and efficiency by getting over it. The factors of swaying, as fellow; - wave caused by vessels around moving - wind and wave caused by weather change - vessel´s moving by change of load weight - tide - move of vessel According to ...

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2005.10a
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• pp.263-268
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• 2005

Nowadays, the vessel size is tending to be bigger and bigger, so port facilities are following this trend, which has been shown inthe competition of Hub-Port among the main ports such as Port of Busan and Port of Shanghai. But there are limited numbers of large container vessels and $70\%$ of the call ships at Busan port are middle and small sized ships which are less than 20,000ton. So we need to consider the handling facilities for these sized ships, but it has disregarded. In this paper, we estimate the optimum level of crane and labor according to vessel's size by container handling cost value reflecting size of vessel; size and number of crane and labor structure.

• Journal of Ocean Engineering and Technology
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• v.25 no.4
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• pp.7-11
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• 2011

The installation phase for a topside module suggested can be divided into 9 stages, which include start, pre-lifting, lifting, lifted, rotating, positioning, lowering, mating, and end of installation. The transfer of the topside module from a transport barge to a crane vessel takes place in the first three stages, from start to lifting, while the transfer of the module onto a floating spar hull occurs in the last three stages, from lowering to the end. The coupled multi-body motions are calculated in both calm water and in irregular waves with significant wave height (1.52m), with suggested force equilibrium diagrams. The effects of the hydrodynamic interactions between the crane vessel and barge during the lifting stage have been considered. The internal forces caused by the load transfer and ballasting are derived for the lifting phases. The results of these internal forces for the calm water condition are compared with those in the irregular sea condition. Although the effect of pitch motion on the relative vertical motion between the deck of the floating structure and the topside module is significant in the lifting phases, the internal force induced pitch motion is too small to show its influence. However, the effect of the internal force on the wave-induced heave responses in the lifting phases is noticeable in the irregular sea condition because the transfer mass-induced draught changes in the floating structure are observed to have higher amplitudes than the external force induced responses.

• Special Issue of the Society of Naval Architects of Korea
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• 2015.09a
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• pp.1-8
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• 2015

In general, the strength assessment for heavy lift vessel is carried out under two stages. The first stage is to comply with the requirement of KR (Korean Register of Shipping) Steel Barges and Rules for Classification of Steel Ships. At the second stage, the structural strength analysis by Finite Element Method is peformed. This paper describes the strength assessment considering various loads for the heavy lift vessel of sheerleg type.

• Ocean Systems Engineering
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• v.12 no.4
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• pp.413-437
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• 2022

An innovative concept for wet-transportation and stepwise installation of mono-bucket foundation for 15 MW offshore wind turbine is proposed. Case studies for two different mono-bucket and wrap-buoy dimensions are conducted and their hydrostatic and hydrodynamic performances are compared for both wet-towing and lowering operations. The intact stability and transient responses are analyzed in detail for various stages of lowering operation. Wave-induced motion statistics during wet tow in sea state 4 (highest operational window) are checked. The proposed concept is found to be feasible and can be an alternative cost-effective solution without using heavy-lift crane vessel in practice.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1116-1120
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• 2004

In the nuclear power plant, there are several cylindrical vessels such as reactor vessel, pressuriser and so on. The vessels are usually constructed by welding large rolled plates, forged sections or nozzle pipes together. In order to assure the integrity of the vessel, these welds should be periodically inspected using sensors such as ultrasonic transducer or visual cameras. This inspection is usually conducted under water to minimize exposure to the radioactively contaminated vessel walls. The inspections have been performed by using a conventional inspection machine with a big structural sturdy column, however, it is so huge and heavy that maintenance and handling of the machine are extremely difficult. It requires much effort to transport the system to the site and also requires continuous use of the utility's polar crane to move the manipulator into the building and then onto the vessel. Setup beside the vessel requires a large volume of work preparation area and several shifts to complete. In order to resolve these problems, we have developed an underwater mobile robot guided by the laser pointer, and performed a series of experiments both in the mockup and in the real reactor vessel. This paper introduces our robotic inspection system and the laser guidance of the mobile robot as well as the results of the functional test.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.87-92
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• 2003

Generally, in jack up rig design for harsh environment, its leg height is a major factor for achieving a sufficient serviceability & operability in terms of the worst environment and the workable depth. Due to difficulties in constructing such a high-slender leg, inaccessibility of yard fabrication equipment, etc. the construction of Jack up rig fur harsh deep sea has not been common. Method using heavy crawler crane, fabrication tower or extension by the floating crane vessel is still conventional construction but, considering high cost fur mobilizing heavy lift vessel (HLV) or additional marine work for implementing preload / full height test at sea, the ground-base construction is much advantageous. Air skidding method (ASM hereafter) is ground-based construction methodology, newly developed due to such requests. ASM could also be extended to similar engineering fields. This paper presents the operating sequence, design parameters and procedure which were verified through successful operation at the end of May 2002.

• Journal of Ocean Engineering and Technology
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• v.25 no.4
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• pp.1-6
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• 2011

The installation of a topside structure can be categorized into the following stages: start, pre-lifting, lifting, lifted, rotating, positioning, lowering, mating, and end of installation. The transfer of the module onto the floating spar hull occurs in the last three stages, from lowering to the end. The coupled multi-body motions are calculated in both calm water and in irregular waves with a significant wave height (1.52m). The effects of the hydrodynamic interactions between the heavy lifting vessel and the spar hull during the lowering and mating stages are considered. The internal forces caused by the load transfer and ballasting are derived for the mating phases. The results of the internal forces for the calm water condition are compared with those in the irregular sea condition. Although the effect of the pitch motion on the relative vertical motion between the deck of the floating structure and the topside module is significant in the mating phases, the internal force induced pitch motion is too small to have this influence. However, the effect of the internal force on the wave-induced heave responses in the mating phases is noticeable in the irregular sea condition because transfer mass-induced draught changes for the floating structure are observed to have higher amplitudes than the external force induced responses. The impacts of the module on the spar hull in the mating phase are investigated.

• Journal of Intelligence and Information Systems
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• v.15 no.3
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• pp.119-136
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• 2009

According to the increase of container flows and the appearance of large-sized container vessels, the container handling equipment in ports is evolving continuously. This research introduces the simulation model for evaluating in detail the mechanical productivity of container cranes. The model considers a single trolley and dual trolleys as the mechanism of a container crane and a single lift, a twin lift, and a tandem lift as the spreader type of it. Additionally, the detail specifications such as the dimension and the speed of a container crane are inputted and the kinematic characteristics of it are simulated. The model also considers the size of a vessel, the storage position of containers in the vessel, and the weight of containers as external physical constraints. Experimental conditions can be configured conveniently because various parameters in the model are separated. Moreover, the model can accommodate flexibly new equipment types and the changes of the existing equipment because it is designed and developed in object-oriented concept.

• International Journal of Naval Architecture and Ocean Engineering
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• v.9 no.1
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• pp.45-54
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• 2017

The purpose of this study is to evaluate various means of wind power turbines installation in the Korean west-south wind farm (Test bed 100 MW, Demonstrate site 400 MW). We presented the marine environment of the southwest offshore wind farm in order to decide the appropriate installation vessel to be used in this site. The various vessels would be WTIV (Wind turbine installation vessel), jack-up barge, or floating crane ${\cdots}$ etc. We analyzed the installation cost of offshore wind turbine and the transportation duration for each vessel. The analysis results showed the most suitable installation means for offshore wind turbine in the Korean west-south wind farm.