signal u03bc k applied thereto the output of multiplier 152 is connected to an input to a multiplier 154 whose other input has the error signal from error function generator 18 applied thereto the output of multiplier 154 represents the resultant u03b4 k of equation 7 the output of multiplier 154 is connected to the input of a multiplier 156 signal w jk n which represents the output of fig7 is applied to a time delay 158 whose output is connected to the other input to multiplier 156 all of the outputs from similar multipliers 156 are connected to a summer 160 similarly all of the outputs from similar multipliers 160 are connected to the inputs to a summer 162 whose output is connected to an input to a multiplier 164 the output from divider 112 which represents out j is connected to the negative input to a subtracter 166 whose positive input is connected to a signal representing unity the output of subtracter 166 is connected to a multiplier 168 whose other input has a signal representing out j applied thereto the output of multiplier 168 is connected to an input to multiplier 164 the output of multiplier 164 represents u03b4 j of equation 8 the input d i shown as r i is connected to an input to a multiplier 170 whose other input is connected to a signal representing u03b7 the output of multiplier 170 is connected to an input to a multiplier 172 whose other input is connected to the.