As a typical example, JR East introduced mini-Shinkansen lines in the following way, without constructing new railways meeting Shinkansen specifications (full specifications): Existing regular railways were modified, new train-cars dedicated for the railways were manufactured and these trains were enabled for operation through both Shinkansen lines and regular railway lines.
後者の代表として、JR東日本は新幹線規格（フル規格）の線路を新規に建設することなく、既存の在来線を改良し、専用の車両を新造したうえで、新幹線と在来線が直通運転できるようにしたミニ新幹線を整備した。