Tetsuya Yao is Professor Emeritus of Osaka University, Professor Emeritus of Hiroshima University and Technical Advisor at Tsuneishi Shipbuilding Co., Ltd. He received his BSc, MSc, and PhD in Engineering at Osaka University with a focus on Naval Architecture. His main fields of research include Structural Mechanics, Structural Analysis, Optimal Design, and Fracture Mechanics particularly in relation to buckling/plastic collapse behavior and strength of steel plated structures.Masahiko Fujikubo is Professor in Structural Integrity Laboratory in Department of Naval Architecture and Ocean Engineering, Osaka University. He received his BSc, MSc, and PhD in Engineering at Osaka University with a focus on Naval Architecture. After obtaining his master degree, he worked for the Nippon Steel Cooperation as an engineer. He was then employed as research assistant by Hiroshima University. Upon receiving his doctoral degree from Osaka University, he became associate professor in 1989 and professor in 1999. My research area is the ultimate strength of ships and offshore structures. He was involved in the development of very large floating structures (VLFS), such as a floating airport and wrote several books related to the structural strength and design of ships and offshore structures including VFFS.