The Rift equations
From Tardis Wiki, the free Doctor Who reference
Toshiko Sato developed The Rift equations to serve as guidelines to operate the Manipulator. With the possible exception of Jack Harkness (TV: Captain Jack Harkness) and John Hart, (TV: Exit Wounds) who had come from a more technologically advanced time, of all of the Torchwood Three team, Tosh seemed to have the greatest understanding of how to operate the machine. (TV: Captain Jack Harkness)