• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2010.05a
• /
• pp.699-701
• /
• 2010

For the development of surveillance Multi Sensor and IFOG, development of integrated surveillance camera for day and night time of its system Control Unit design and navigation device interlocking system was made. Control Unit analysis of integrated ship system began with selection of control unit related to feasible navigation device list.After sorting navigation equipment list, applications, features, connection methods, communication methods, data type of control unit and data direction between navigation equipments and the data types of each navigation equipment is sorted to observe its performance.

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

• Journal of Navigation and Port Research
• /
• v.26 no.3
• /
• pp.275-280
• /
• 2002

Vessel collision accidents have been investigated by means of questioning the persons involved and plotting manually the stated situation. But the repetitive plotting by hand can cause the investigator or to make some errors, and it can be connected to a wrong judgement. In this paper, we proposed a simulator for reconstructing and analyzing vessel collision accidents at sea, where the given situation is plotted automatically on it. We verified the validity of the system by applying it to some collision accidents.

• Structural Engineering and Mechanics
• /
• v.20 no.4
• /
• pp.451-463
• /
• 2005

Structural members commonly employed in marine and off-shore structures are usually fabricated from plates and shells. Collision of this class of structures is usually modeled as plate and shell structures subjected to dynamic impact loading. The understanding of the dynamic response and energy transmission of the structures subjected to low velocity impact is useful for the efficient design of this type of structures. The transmissions of transient energy flow and dynamic transient response of these structures under low velocity impact are presented in the paper. The structural intensity approach is adopted to study the elastic transient dynamic characteristics of the plate structures under low velocity impact. The nine-node degenerated shell elements are adopted to model both the target and impactor in the dynamic impact response analysis. The structural intensity streamline representation is introduced to interpret energy flow paths for transient dynamic response of the structures. Numerical results, including contact force and transient energy flow vectors as well as structural intensity stream lines, demonstrate the efficiency of the present approach and attenuating impact effects on this type of structures.

• Proceedings of KOSOMES biannual meeting
• /
• 2008.05a
• /
• pp.197-204
• /
• 2008

The right of hot pursuit is an exception to the general rule that a ship on the high seas is subject to the jurisdiction of the state whose flag she flies. The right of hot pursuit is provided in the United Nations Convention on the Law of the Sea. This paper discusses the requirements of the right of hot pursuit. The use of force should be avoided during hot pursuit. When force is unavoidable, that is not go beyond what is reasonable and necessary in the circumstances.

• Journal of the Society of Naval Architects of Korea
• /
• v.43 no.1 s.145
• /
• pp.87-95
• /
• 2006

There are hundreds of ship blocks which are under the block assembly, painting, and outfitting assembly works in the pre-erection shops of shipyard. Generally, each block is planned to be processed in a pre-erection shop according to the block type by the long-term production-scheduling before six months. However, many blocks can't be processed in the planned time and the planned shop since the before and after block-processing changes or delays the planned sequential works in pre-erection shops. Therefore, it is essential to monitor the current location of each block and work in process to cope with the changed situation of pre-erection shops. Present study integrates PDA, GPS, and CDMA not only to chase the location of each block but also to exchange the pre-erection work order and the work report between the production-scheduling server and the production managers in the pre-erection shops. This study shows a prototype for the block tracing and process monitoring in the pre-erection shops.

• Journal of Ship and Ocean Technology
• /
• v.7 no.4
• /
• pp.16-31
• /
• 2003

The finite volume based multi-block RANS code, WAVIS developed at KRISO, is used to simulate the turbulent flows around a submarine with the realizable $\textsc{k}-\varepsilon$ turbulence model. RANS methods are verified and validated at the level of validation uncertainty 1.54% of the stagnation pressure coefficient for the solution of the turbulent flows around SUBOFF submarine model without appendages. Another SUBOFF configuration, axisymmetric body with four identical stem appendages, is also computed and validated with the experimental data of the nominal wake and hydrodynamic coefficients. The hydrodynamic forces and moments for SUBOFF model and a practical submarine are predicted at several drift and pitch angles. The computed results are in extremely good agreement with experimental data. Furthermore, it is noteworthy that all the computations at the present study were carried out in a PC and the CPU time required for 2.8 million grids was about 20 hours to get fully converged solution. The current study shows that CFD can be a very useful and cost effective tool for the prediction of the hydrodynamic performance of a submarine in the basic design stage.

• Journal of the Society of Naval Architects of Korea
• /
• v.42 no.5 s.143
• /
• pp.448-457
• /
• 2005

The experiment was performed at the large wind tunnel of the Chungnam National University to measure the velocity distribution around the stern of a Liquefied Natural Gas Carrier model. The data, mean velocity vectors of turbulent shear flows at the stern and near-wake including the propeller plane, were obtained by a five-hole Pilot tube for the double body model fixed inside the wind tunnel test section. The present result of the double body model shows a close agreement with the result of the lowing tank experiment performed by the KRISO for the same ship model. The characteristics of the LNG stern flow are discussed based on the measured velocity distribution. The data can be very useful for the validation of some numerical methods in computational fluid dynamics.

• Journal of the Society of Naval Architects of Korea
• /
• v.46 no.6
• /
• pp.611-621
• /
• 2009

This paper first reviews the physical meanings and the expressions of two representative strain rate models: CSM (Cowper-Symonds Model) and JCM (Johnson-Cook Model). Since it is known that the CSM and the JCM are suitable for low-intermediate and intermediate-high rate ranges, many studies regarding marine accidents such as ship collision/grounding and explosion in FPSO have employed the CSM. A formula to predict the material constant of the CSM is introduced from literature survey. Numerical simulations with two different material constitutive equations, classical metal plasticity model based on von Mises yield function and micromechanical porous plasticity model based on Gurson yield function, have been carried out for the stiffened plates under impact loading. Simulation results coincide with experimental results better when using the porous plasticity model.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.7 no.6
• /
• pp.979-994
• /
• 2015

The mode shapes of a segmented hull model towed in a model basin were predicted using both the Proper Orthogonal Decomposition (POD) and cross random decrement technique. The proper orthogonal decomposition, which is also known as Karhunen-Loeve decomposition, is an emerging technology as a useful signal processing technique in structural dynamics. The technique is based on the fact that the eigenvectors of a spatial coherence matrix become the mode shapes of the system under free and randomly excited forced vibration conditions. Taking advantage of the simplicity of POD, efforts have been made to reveal the mode shapes of vibrating flexible hull under random wave excitation. First, the segmented hull model of a 400 K ore carrier with 3 flexible connections was towed in a model basin under different sea states and the time histories of the vertical bending moment at three different locations were measured. The measured response time histories were processed using the proper orthogonal decomposition, eventually to obtain both the first and second vertical vibration modes of the flexible hull. A comparison of the obtained mode shapes with those obtained using the cross random decrement technique showed excellent correspondence between the two results.