• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.2
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• pp.119-127
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• 2012

A wire rope is comprised of several metal wires which are wound together like a helix and it can resist relatively large axial loads, as compared with bending and torsional loads. A shipbuilding crane for erection such as a floating crane, a gantry crane, and a crawler crane hoists up and down heavy blocks by using these wire ropes. Thus, it is necessary to find dynamic properties of a wire rope in order to safely lift the blocks using the crane. In this study, a formula for calculating the tension and torsional moment acting on wire ropes of the crane was derived based on the existing study, and then dynamic simulation of the crane was performed based on the formula. The result shows that the dynamic simulation can be applied to find the safe method for block erection of shipyards.

• Bulletin of the Society of Naval Architects of Korea
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• v.48 no.4
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• pp.14-17
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• 2011

• 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 the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.3680-3684
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• 2015

A deck crane is installed on the deck of a ship by lifting method using tower crane or floating crane. The safety assessment for two points lifting method should be preceded to ensure a safe installation of deck crane. In this study, finite element models of deck crane and fixing jig are generated for the structural analysis which can evaluate a safety of lifting method. Also, reaction forces and boundary conditions considering lifting state are applied to the structural analysis. The proposed safety assessment method can be useful as an analytic tool that can provide a safer procedure for installation of deck crane by lifting method.

• Computational Structural Engineering
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• v.26 no.1
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• pp.66-74
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• 2013

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.11a
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• pp.288-290
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• 2004

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.569-575
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• 2022

It is most desirable to build a crane training program in the same evvironment as the actual port, but it has problem such as time constraint and cost. To overcome these limitations, next-generation training programs based on AR/VR are receiving a lot of attention. In this paper, a prototype of a harbor crane training system based on virtual reality was designed and implemented. The system implemented in this paper consists of two elements: an Arduino-based IoT terminal and an HMD equipped with a Unity application program. The IoT terminal consists of 2 controllers, 2 toggle switches, and 8 button switches to process data generated according to the user's operation. The HMD uses Oculus Quest2 and is connected to the IoT terminal through wireless communication to provide user convenience. The training system implemented in this paper is expected to provide trainees with a training environment independent of time and place through virtual reality and to save time and money.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2010.04a
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• pp.211-212
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• 2010

하역장치가 장착된 모바일하버 선박은 새로운 해상운송시스템 개념으로, 임시정박지에서 대형 컨테이너 선박에 계류하여 해상상태 3 이하 조건에서 선박간 해상계류 상태에서 신속하면서 효율적인 컨테이너 하역작업을 수행하는 것이다. 모바일하버와 관련한 주요 연구로는 고속하역시스템, 부유체 구조 설계, 안벽하역시스템 해석 및 작업크레인 설계 둥의 원천 기술 개발을 중심으로 수행되었다. 본 연구는 모바일하버 선박의 하역작업 중 동척 안전성 확보를 위한 계류안정화시스템을 개발하고자 하는 것으로, 국내외 계류장치에 대한 현황 분석을 기초로 현재 선박에 탑재되어 있는 의장장치인 윈치시스템에 계류안정화 기능을 추가시킨 포지셔녕 윈치를 개발하여 모선과의 상대운동을 최소화하는 방안에 대한 개념 설계를 제안한다.

• Korean Journal of Computational Design and Engineering
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• v.15 no.1
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• pp.70-83
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• 2010

Recently, floating cranes are mainly used to erect heavy blocks or cargos for constructing ships in many shipyards. It is important to estimate the dynamic motion of the heavy cargo suspended by a floating crane and the tension of the wire ropes between the floating crane and the heavy cargo. In this paper, the coupled dynamic equations of motion are set up for considering the 6 degree-of-freedom floating crane and the 6-degrees-of-freedom heavy cargo based on multibody system dynamics. Depending on the cargo weight, the motion of the floating crane would be changed to nonlinear state. The nonlinear terms in the equation of motion are considered. In addition, the nonlinear hydrostatic force, the linear hydrodynamic force, wire rope force, mooring force and gravity force are considered as the external forces. As the result of this paper, we analyze the engineering effect for erecting the heavy cargo by using the floating crane.

• Journal of Navigation and Port Research
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• v.34 no.5
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• pp.311-317
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• 2010

Mobile Harbor(MH) is a new paradigm for maritime transport system introduced in Korea, the target of which is to carry out ship-to-ship cargo operation rapidly and effectively even under a condition of sea state 3. A MH ship is moored alongside a large container vessel anchored at the defined anchorage and also equipped with gantry cranes for handling containers. The MH study concerned includes rapid container handling system, optimum design for floating structure, hybrid berthing & cargo operation system, design for cargo handling crane, etc. This paper is to deal with a conceptual design of a stabilized mooring system and mooring equipment under a condition of ship-to-ship mooring. In this connection, we suggest a positioning control winch system in order to control heave motions of the MH ship which is to add constant brakepower and stabilized function to an auto-tension winch and mooring equipment used currently in large container ships.