"Estimator 1 is described by the following equations in which the letters A, B, C indicate discrete forms of the matrices discussed above: x ^ 1 , j + 1 = A 240 x ^ 1 , j + B 240 u k + K 240 ( C 240 x ^ 1 , j - y _ j + ) , x ^ 1 ( j _ T 240 ) = IC 1 y ^ 1 , j = C 240 x ^ 1 , j Where" . . . . .