(1) 2015-008434, Radiation therapy system and treatment program, 2015 January, Hokkaido Univ., Shimizu S, Matsuura T, Takao S, Umegaki K, Katoh T et al.

(2) 2015-023202, Image processing unit and Particle beam therapy system equipped with image processing unit, 2015 February, Hitachi Ltd. and Hokkaido Univ., Umegaki K, Takao S et al.

(3) 2016-32729, Particle beam therapy system and ridge filter, and method of manufacture of the ridge filter, 2016 February, Hitachi Ltd. and Hokkaido Univ., Matsuura T, Umegaki K et al.

(4) 2016-69463, Particle Beam Dose Evaluation System, Planning Device, Particle Beam Irradiation System, And Dose Evaluation Method, 2016 March, Hitachi Ltd. and Hokkaido Univ., Matsuura T, Umegaki K, Shirato H et al.