• Korean Journal of Computational Design and Engineering
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• v.19 no.3
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• pp.203-213
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• 2014

The O&M (Operation and Maintenance) phase of offshore plants with a long life cycle requires heavy charges and more efforts than the construction phase, and the occurrence of an accident of an offshore plant causes catastrophic damage. So previous studies have focused on design for reliability, and recently many studies have dealt with a maintenance system to prevent unexpected failures. Nowadays due to the emerging ICTs (Information Communication Technologies) and sensor technologies, it is possible to send health monitoring information of important equipment to administrator of an offshore plant in real time, which leads to having much concern on condition based maintenance policy or predictive maintenance. In this study, we have reviewed previous studies associated with condition-based maintenance of offshore plants, and introduced the approaches predicting failures of the compressor which is one of essential mechanical devices in LNG FPSO.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.4
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• pp.12-23
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• 2014

The O&M (Operation and Maintenance) phase of offshore plants with a long life cycle requires heavy charges and more efforts than the construction phase, and the occurrence of an accident of an offshore plant causes catastrophic damage. So previous studies have focused on the development of advanced maintenance system to avoid unexpected failures. Nowadays due to the emerging ICTs (Information Communication Technologies) and sensor technologies, it is possible to gather the status data of equipment and send health monitoring data to administrator of an offshore plant in a real time way, which leads to having much concern on the condition based maintenance policy. In this study, we have reviewed previous studies associated with CBM (Condition-Based Maintenance) of offshore plants, and introduced an algorithm predicting the next failure time of the compressor which is one of essential mechanical devices in LNG FPSO (Liquefied Natural Gas Floating Production Storage and Offloading vessel). To develop the algorithm, continuous time Markov model is applied based on gathered vibration data.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.2
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• pp.233-239
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• 2016

In this paper, a maintenance system is developed for LNG-FPSO topside and hullside equipment based CBM (Condition Based Maintenance) methodology. First, the development system defined the PWBS(Product Work Breakdown Structure) of major equipment of LNG-FPSO. Second, the development system developed the failure analysis, economic evaluation for optimal maintenance plan and database systems that save and manage information about equipment, failure mode, failure rate and failure cause. Finally, the verification of the development system was applied to the inlet system of topside and the pump tower system of hullside and the system was confirmed the effectiveness of CBMS(Condition Based Maintenance System).

• Journal of Advanced Marine Engineering and Technology
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• v.36 no.5
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• pp.574-579
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• 2012

This paper presents the new cascade liquefaction cycles using $CO_2-C_2H_6-N_2$ and $CO_2-N_2$. The performance and exergy of cascade liquefaction cycles are analyzed using HYSYS software and then confirmed the possibility of these cycles for LNG-FPSO ship. From the comparison of performance and exergy loss of these cycles, the cascade liquefaction cycles using $CO_2-C_2H_6-N_2$ showed higher performance and the cycle using $CO_2-N_2$ presented higher exergy loss. The cascade liquefaction cycle using $CO_2-N_2$ is lower efficiency and higher compressor work compared to the optimized cascade liquefaction cycle using $C_3H_8-C_2H_4-C_1H_4$. But, if the efficiency of $N_2$ cycle in these liquefaction cycles is improved, it is possible to apply the cascade liquefaction cycle using $CO_2-C_2H_6-N_2$ and $CO_2-N_2$ to LNG-FPSO ship due to the simple composition device of these cycles.