해양탐사선의 수중 방사 소음 규제(ICES CRR 209) 대응 및 실효적인 탄소 저감(Carbon Reduction)을 위해, 본 연구는 336 GT급 기계식 추진 기준선을 모델로 수소 연료전지 하이브리드 선박 대체 건조를 위한 공간 배치 최적화와 역학적 타당성을 검증하였다. 상사 법칙을 적용해 요구 선속을 12 kn로 하향하고, 단기 거점 연계 운항(Hub-and-Spoke)을 새로운 DRM으로 수립하여 1일 수소 요구량을 397 kg 으로 최적화함으로써 20 ft 저장 모듈 1기 탑재를 실현하였다. 특히 IGF Code 준수와 시야 확보를 위해 선수 좌현에 편심 배치된 15 ton 수 소 저장 모듈의 횡경사 문제를 해결하고자 비대칭 하중 상쇄(Asymmetric Load Compensation) 방법론을 제안하였다. 중량-모멘트 해석 결과, 고정 평형수 없이 TCG를 +0.009 m로 수렴시켜 완벽한 수평 상태(Zero-Heel)를 달성했으며, VCG 상승폭을 0.172 m로 억제하고 선미 트림 (Trim by Stern)을 구현해 선박의 예비 부력과 복원성을 성공적으로 방어하였다. 결론적으로 본 연구는 기존선 규모 제약 속에서도 완전한 무탄소 선박으로 나아가기 위한 브릿지 기술(Bridge Technology)로서, 수소 하이브리드 관공선 대체 건조의 역학적 실현 가능성을 입증하 였다.

A timber lattice roof, which has around 30m span, was constructed. In order to figure out the realistic buckling load level, the structural analysis of this roof structure was performed especially by stiffness of connection with various asymmetric snow load. Due to the characteristics of application of snow load, the load combinations of snow should be considered not only global area but also local part so that the critical buckling load could be observed as easy as possible. Geometrical imperfection was simulated to consider inaccurate shape of structure. And then nonlinear analysis were performed. Finally, this paper could investigate that the asymmetric snow load with the lower level stiffness of connection decreased the level of buckling load significantly.

A single-layerd steel lattice roof, which has 50m span, was constructed. In order to figure out the realistic buckling load level, the structural analysis of this roof structure was performed especially by local snow load. Due to the characteristics of application of snow load, the load combinations of snow should be considered not only global area but also local part so that the critical buckling load could be observed as easy as possible. Geometrical imperfection was simulated to consider inaccurate shape of structure. And then nonlinear analysis were performed. Finally, this paper could investigate that the local snow load with geometrical imperfection decreased the level of buckling load significantly.

The purpose of this paper is to suggest the strategical lifting postures able to alleviate imbalanced EMG amplitude leading to an increase in low back muscle fatigue while lifting asymmetric load dynamically. Eleven male subjects are required to lift symm

This study is aimed to show that an asymmetric load in the frontal plane leads to an increase in low back loading and fatigue in comparison with a symmetric load when workers lift an external weight by investigating previous studies and verifying the phen

The structure system that is discreterized by continuous shells is usually used to make a large space structures and these structures show the collapse mechanisms that are captured at over the limit load, and snap-through and bifurcation are most well known of it. For the collapse mechanism, rise-span ratio, element stiffness and load mode are main factor, which it give an effect to unstable behavior. Moreover, resist force of structure can be reduced by initial condition and initial imperfection significantly. In order to investigate the instability of shell structures, the finite deformation theory can be applied and it becomes a nonlinear mathematics in which use equation of tangential stiffness incrementally. With an initial imperfection, using simple example and Flow Truss Dome, the buckling characteristics of space truss is main purpose of this paper, and unstable behavior is studied by proposed the numerical method. Also, by using MIDAS, this research work analyzes displacements and inner forces as the design load of model, and the ratio of buckling load of design load is investigated.