본 논문에서는 다목적 구조물인 다중연결 해양부유체를 대상으로 변형 기반 모드 차수축소법을 적용하고 차수축소모델의 구조응 답 예측 성능을 향상시키기 위해 유전 알고리즘 기반의 센서 배치 최적화를 수행하였다. 다중연결 해양부유체의 차수축소모델 생성 에 필요한 변형 기반 모드 데이터를 얻기 위해 다양한 규칙파랑하중조건에 대한 유체-구조 연성 수치해석을 수행하고 변형 기반 모드 의 직교성, 자기상관계수를 이용하여 주요 변형 기반 모드를 선정하였다. 다중연결 해양부유체의 경우 차수축소모델의 구조응답 예 측 성능이 계측 및 예측 구조응답 위치에 따라 민감하기 때문에 유전 알고리즘 기반의 최적화를 수행하여 최적의 센서 배치를 도출하 였다. 최적화 결과, 모든 센서 배치 조합에 대한 차수축소모델 생성 및 예측 성능 평가 대비 약 8배의 계산 비용을 절감하였으며, 예측 성능 평가 지표인 평균 제곱근 오차가 초기 센서 배치보다 84% 감소하였다. 또한, 다중연결 해양부유체 모형시험 결과를 이용하여 불 규칙파랑하중에 대한 최적화된 센서 배치의 차수축소모델의 구조응답 예측 성능을 평가 및 검증하였다.

Structural health monitoring for ships and offshore structures is important in various aspects. Ships and offshore structures are continuously exposed to various environmental conditions, such as waves, wind, and currents. In the event of an accident, immense economic losses, environmental pollution, and safety problems can occur, so it is necessary to detect structural damage or defects early. In this study, structural response data of multi-linked floating offshore structures under various wave load conditions was calculated by performing fluid-structure coupled analysis. Furthermore, the order reduction method with distortion base mode was applied to the structures for predicting the structural response by using the results of numerical analysis. The distortion base mode order reduction method can predict the structural response of a desired area with high accuracy, but prediction performance is affected by sensor arrangement. Optimization based on a genetic algorithm was performed to search for optimal sensor arrangement and improve the prediction performance of the distortion base mode-based reduced-order model. Consequently, a sensor arrangement that predicted the structural response with an error of about 84.0% less than the initial sensor arrangement was derived based on the root mean squared error, which is a prediction performance evaluation index. The computational cost was reduced by about 8 times compared to evaluating the prediction performance of reduced-order models for a total of 43,758 sensor arrangement combinations. and the expected performance was overturned to approximately 84.0% based on sensor placement, including the largest square root error.

1. 서 론
2. 다중연결 해양부유체 계측센서 배치 최적화
    2.1 다중연결 해양부유체 유체-구조 연성 수치해석
    2.2 축소전환행렬 기반 구조응답 평가
    2.3 가상 센서 배치 최적화
    2.4 센서 배치 최적화 결과
    2.5 모형시험 계측 결과 비교
3. 결 론
감사의 글
References
요 지

• 심기찬(과학기술연합대학원대학교 선박해양플랜트연구소스쿨 박사과정) | Kichan Sim (Graduate Student, Korea Research Institute of Ships & Ocean Engineering School, University of Science & Technology, Daejeon, 34113, Korea)
• 이강수(과학기술연합대학원대학교 선박해양플랜트연구소스쿨 교수, 선박해양플랜트연구소 친환경해양개발연구본부 책임연구원) | Kangsu Lee (Professor, Korea Research Institute of Ships & Ocean Engineering School, University of Science & Technology, Daejeon, 34113, Korea, Principal Researcher, Department of Eco-friendly Ocean Development Research Division, Korea Research Institute of Ships & Ocean Engineering, Daejeon 34103, Korea) Corresponding author