 Parametrons continued to be used for computing in Japan until the 1960s when they gave way to transistors.The quantum flux parametron is a later improvement of the parametron, also by Goto, that uses superconducting Josephson junctions to improve both the speed and the energy consumption of these devices.During his visit to MIT in 1961, Goto devised the first time-optimal solution to the firing squad synchronization problem, a problem of designing a cellular automaton in which all cells simultaneously fire, starting from an initial configuration with only one active cell.