I am researching various phenomena from the modeling, mathematical anaysis and numerical analysis points of view. The phenomena which I have treated so far are, for example, ice-water phase transition, groundwater flow, competition and/or cooperation of animal species, deep geological repositories of radioactive waste, crystal growth and so on. Recently, I am very interested in cell-cell adhesion and cell sorting phenomena in life sciences. I constructed both macro- and microscopic models for these phenomena, and apply them to elucidate real problems in life sciences.