amplifiers managed develop stable negative feedback amplifiers harry nyquist developed nyquist stability criterion feedback systems richard bellman developed dynamic programming since warren e dixon control theorist professor andrey kolmogorov co developed wiener kolmogorov filter norbert wiener co developed wiener kolmogorov filter coined term cybernetics john r ragazzini introduced digital control use z transform control theory invented laplace lev pontryagin introduced maximum principle bang bang principle pierre louis lions developed viscosity
Applied science Business Systems science Control theory