Prof. Shibutani is an expert in solid mechanics, in particular the defect theory of materials and plasticity from a multiscale view and nondestructive observation techniques. His presentation sought to address the challenge of modeling plastic deformation at various length scales, focusing on the interaction between dislocations and grain boundaries through three possible approaches: mm-sized tensile testing, nm-sized molecular dynamics simulations, and µm-sized crystal plasticity finite element analysis, all aimed at understanding the impact of dislocation-GB interactions on grain interior behavior.