I have finished my Ph.D. defense at The University of Tokyo. The dissertation title is “Systematic Study of Escape Processes of Cosmic Rays from Supernova Remnants based on Gamma-ray and Thermal X-ray Properties”. I have studied how accelerated particles diffuse from their acceleration sites, supernova remnants, through X-ray and gamma-ray observations. To quantitatively use ages of supernova remnants, I have done a study to “calibrate” their age estimations as well. These works will be published as several papers. The Ph.D. program was somewhat hard but was mostly fun.