Journal of the Society of Naval Architects of Korea (대한조선학회논문집)

The Society of Naval Architects of Korea (대한조선학회)
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A Study on the Design Sea-state Determination Using the IFOSM Method

역 일계이차 모멘트법을 이용한 설계 해상상태의 결정에 관한 연구

  • Lee, Jae-Ohk (Hyundai Maritime Research Institute, Hyundai Heavy Industries) ;
  • Rho, Jun-Bumn (Hyundai Maritime Research Institute, Hyundai Heavy Industries)
  • 이재옥 (현대중공업 선박해양연구소) ;
  • 노준범 (현대중공업 선박해양연구소)
  • Received : 2000.03.15
  • Accepted : 2010.05.06
  • Published : 2010.06.20
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Abstract

Response-based approach is getting more preferred in determining the design sea-state for offshore structures because traditional environment-based approach is known to yield a much conservative design condition. This paper introduces the inverse first-order second-moment (IFOSM) method as a response-based approach, which is expected to give a more feasible design condition at the cost of reasonable number of motion analyses. The IFOSM method is based on the theory of probability and adopts an optimization scheme to determine the design point. Both the design maximum response and design sea state can be obtained straightforwardly from the optimum. The IFOSM method has been applied to a turret-moored FPSO's design problem and showed its effectiveness in practical use.

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