... analytical designmethods, namely abstraction, linearisation and simplification, e.g. Allen [13].Mathematical models imbedded in today’s simulation software provide a means to handle both variations ... Tyr´eus and EdLongwell from DuPont, and Paul Fruehauf from Applied Control Engineering. Thesegentlemen share a passion for the field and a commitment to the practical approach to both teaching and ... L)e−LsThe Laplace variable s is replaced by jω and converted to polar form. Then theamplitude ratio (AR) and phase α are computed via Equations 3.80 and 3.81:AR =1√ω2τ2+ 1(3.80)α = tan−1(−ωτ)...