• Special Issue of the Society of Naval Architects of Korea
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• 2008.09a
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• pp.33-37
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• 2008

The evidence of the Cargo tank volume is very important between Buyer and Seller for agreement each other for LNG Ship. CTS(Custody Transfer System) Radar type level gauging sensor to be measured for cargo volume. The data of Trim & List sensor to be compensated for measuring data which is original data of the CTS sensor. The latest days, the Buyer would have posed a problem both the location and the accuracy of trim/list sensor specially neared final stage of the ship's delivery. So, we would like to report the introducing to the trim/list sensor and the confirmation of actual location for the trim/list sensor.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.2
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• pp.662-670
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• 2019

Tanker cargo tanks are equipped with the means of raising and maintaining the cargo discharge temperature to a suitable level. In this paper, a new heating coil design is proposed and analyzed. Contrary to conventional designs, wherein the heating coils are evenly distributed over the tank bottom, the proposed design arranges the heating coils in the central part of the tank bottom, in a vertical direction. Due to the intensive cargo circulation generated, a forced convection is superimposed on a buoyancy-driven natural convection, providing a more efficient mixed convection heat transfer mechanism. Numerical simulations performed by using a finite volume method show that in the case of 7-bar steam Bunker C heavy fuel oil heating, a five-hour circulation phase average heat transfer coefficient equals 199.2 W/m²K. This result might be taken as an impetus for the more thorough experimental examination.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.10a
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• pp.189-195
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• 2000

New concept of LNG-FPSO ship with moonpool and bilge step in bottom is considered and investigated in the point of motion reduction and sloshing phenomena of the cargo and operation tanks. The cargo capacity of the ship of which principle dimensions is L x B x D x t(design) =270.0 x 51.0 x 32.32 x 13.7(m) 16K at 98% loading condition. The two moonpools and rectangular step at bilge part are setted up specially for getting the effect of motion decrease. For the motion analysis, linearized three dimensional diffraction theory with the simplified boundary conditions is used. The six-degree of freedom coupled motion responses are calculated for the LNG-FPSO ship. Viscous effects on the roll motion responses of a vessel are taken into account in this calculation program using an empirical formula suggested by Ikeda, Himeno and Tanaka is used. The case study for the moonpool size had been carried out by theoretical estimation and experimental method. For the optimization of the moonpool size and effect of the step, 9 cases of its size and with and without step are considered. From the results of calculation and experiment, it can be concluded that this designed LNG-FPSO ship have possibility to carry out her missions in the rough sea as for the owner's demand waves condition. The motion responses, especially roll motion, for the designed LNG-FPSO ship are much lower than those of another drillship and shuttle tanker and limit criterions are satisfied. For the check of the cargo tank and operation tank sizes we have performed sloshing analysis in the irregular waves which focuses on the pressure distribution on the tank wall and the time history of pressure and free surface for No.2 and No5. tanks of LNG-FPSO with chamfers. Finally we got the tank size which has no resonance and no impact pressure in all filling in the bow quartering and beam sea.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.3
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• pp.421-429
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• 2010

In this paper, in order to analyze the dynamic response of a floating crane when it lifts a heavy cargo, the boom of the floating crane is considered as an elastic beam. The boom is divided into elements based on finite element formulation and the floating frame of reference formulation and nodal coordinates are employed to model the boom as a flexible body. As an extension of the previous study, in order to consider spatial motion in waves, the coupled equations of motions of the 6 degree of freedom (DOF) floating crane and 6 DOF cargo are developed based on the flexible multibody system dynamics. The 3 dimensional deformation of the elastic boom is considered with 18 DOF. The dynamic simulation of the floating crane and the cargo is performed under regular wave conditions with various cargo weights. Finally, the effects of the elastic boom on lifting cargo are discussed by comparing the simulation results between the elastic boom and a rigid boom.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2016.05a
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• pp.207-208
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• 2016

By according to increase the research for autonomous vehicle in automobile industries, the efficient of autonomous cargo truck instead of conventional driver cargo truck will be analyzed in logistics areas. The inland transportation has been serious problem such as traffic accident, traffic congestion in downtown, air pollution, noise and etc. even if it have a great effect to logistics industries. Especially there have to be improved its transportation schedule and sleepy driving in night which induced heavy accident in highway. In this study, the effectiveness of autonomous cargo truck will be analysed by considering the logistics cost including social effects.

• Journal of Korean Port Research
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• v.4 no.1
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• pp.45-57
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• 1990

Today, about 95% of totoal import import and export container cargo in Korea is being transported through the Busan Port. The 59% of these cargos is being handled at BCTOC and the rest is at the existing piers. As the Off-Dock Container Yards(ODCY) within Busna City are located at 33 different places, it causes serious problems in the container cargo transport and inland traffic near Busan district. The container carriers to the inland market or other terminals cause heavy traffics to the Busan Traffic System. Hence, this impacts to the cost of the cargo handling equipment and cargo storage, the usage of labor resources, the control of natural environment etc. To solve those problems, it is required to build Inland Container Depot(ICD) in the Southeastern Economic Area. In this study therefore, we try to calculate the required area of Inland Container Depot(ICD) for Busan Port which deals which deals with the container cargo. We also investigate the sites for ICD being suggested outside of Busan City. We use the Analytic Hierarchy Process(AHP) Method to decide the best one. The result shows that the best is the Site B(Dong Myen, Yangsan Kun).

• Journal of the Society of Naval Architects of Korea
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• v.58 no.1
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• pp.17-23
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• 2021

The membrane-type Liquefied Natural Gas (LNG) cargo tank is equipped with a double barrier to seal the LNG, of which the secondary barrier serves to prevent LNG leakage and mainly uses fiber-reinforced composite materials. However, the composite materials have thermal expansion anisotropy, which deteriorates shape distortion and mechanical performance due to repeated thermal loads caused by temperature changes between cryogenic and ambient during the unloading of LNG. Therefore, in this study, the longitudinal thermal expansion characteristics of the composite materials were obtained using a vertical thermo-mechanical analyzer, and the elastic modulus was obtained through the tensile test for each temperature to perform thermal load analysis for each direction. This is considered that it is useful to secure reliability from the viewpoint of the design of materials for a LNG cargo hold.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.6
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• pp.597-603
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• 2014

The cargo of ships and offshore structures is the number of oil of combustibility and volatile, oil processing cargo. Furthermore heavy cargo of the vehicle or container box or bulk cargo are occupied the remainder of cargo. In addition, there is a possibility to move the location of the cargo and the vessel because it is received periodic / non-periodic a load of wave and ocean current. Therefore a shipboard hazard is much greater than onshore industry hazard. Monitoring and preparation for safety are necessary things because there is always risk of accidents arise from the impact of the freight and cargo of ships and offshore structures. In this study, we conducted a study with respect to the introduction of the wireless sensor network monitoring system to ensure the safety of the crew and workers on shipboard.

• Journal of Biosystems Engineering
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• v.42 no.4
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• pp.235-241
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• 2017

Purpose: It is to develop an agricultural three-directional dumping vehicle that can help farmers reduce intensive labor when carrying heavy loads and for easy dumping. In addition, a novel mechanism was applied for controlling the direction of the tilting cargo box by using a single hydraulic cylinder and simple apparatus. The overturning safety was analyzed to provide safe-use ground slope region of the vehicle to be used at upland fields and orchards. Methods: The developed three-directional dumping vehicle was constructed using a cargo box, vehicle frame, driving components, lifting components, and controller. The novel mechanism of controlling the dumping direction involves the operation of two latching bars, which selectively release or collapse the connecting edge between the vehicle frame and cargo box. A multibody dynamics analysis software (RecurDynV8R5) was used to determine the safe-use ground slope area when tilting the cargo box at slopes. A computer analysis was conducted by increasing the ground slope while rotating the vehicle when the cargo box comprised loads of 300 and 500 kg and stacking heights of 40 and 80 cm, respectively. Results: The three-directional dumping vehicle was successfully manufactured, and the cargo box was tilted at $37^{\circ}$ and $35^{\circ}$ for dumping forward and sideways. The latching bars were manually and selectively collapsed with the vehicle frame to control the dumping direction. When forward dumping, the safe-use ground slope was over $20^{\circ}$ in all vehicle directions and loaded conditions. Conclusions: A three-directional dumping vehicle was developed to reduce labor-intensive work in the farming environment. The user can easily control the dumping direction by using the control panel. The vehicle was safe to be used in most of the Korean upland fields and orchards (area over 96%) for the forward dumping.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.1
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• pp.31-42
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• 2009

Common structural rule (CSR) doesn' t provide any other specific regulations for permanent means of access (PMA) platform structure in a cargo oil tank. The PMA platform is recommended to comply with scantling requirement of local support member. However, it leads to too conservative scantlings compared with actual loads imposed on the platform. This paper proposes a strength assessment procedure for the PMA structure based on a nonlinear ultimate strength. The ultimate strength is evaluated in a sufficiently conservative way. The first linear buckling mode is used as an initial imperfection shape and its magnitude is determined using the definitions of DNV PULS. Since the same imperfection mode as the failure mode of the ultimate limit state is assumed, it can accelerate the failure. Au ultimate strength capacity curve obtained from a series of nonlinear FE analysis is compared with actual stresses calculated by CSR cargo hold analysis.