This operation is done for a fixed period, then its inverse is done for a variable period in a dual-slope analog-to-digital converter. This operation names a neuronal model proposed by Louis (10[1])Lapicque (-5[1])(“la-PEEK”) that makes no assumption about the shape of action potentials. This operation is the second term in the computation done by three-term control systems. (10[4])Ideal (10[2])op-amps (10[4]-5[1])that implement (10[2]-5[2])this (10[1])operation have a transfer function (10[2])of the (-5[1])negative reciprocal (10[1]-5[1])of RC times s, (10[1])since this operation (10[1])in the time domain (-5[1])is Laplace transformed (10[1]-5[1])into division in the s-domain. (10[3]-5[2])A (10[1])capacitor (10[1])performs (-5[2])this mathematical operation to the current, (-5[2])since the charge (-5[1])is (-5[1])equal to this operation with respect (-5[1])to time (-5[1])on (-5[1])the current. (10[3]-5[5])For 10 (-5[1])points, (10[2])name this (10[2])operation from calculus (10[2]-5[2])that gives (10[1]-5[1])the (-5[2])area (10[3])under (10[3])a curve. (10[5])■END■ (10[35]0[2])