Some implications of biquadratic functions in the tolerance problem
J.W. Bandler, P. Liu · IEEE Transactions on Circuits and Systems · 1975
The usual assumptions for the tolerance problem in the frequency domain are that the worst cases occur at boundary points of a tolerance region, and that the acceptable region is simply connected. These assumptions are investigated and conditions for validity are given for the class of networks which have bilinear dependence on the parameter of interest. This paper elaborates on an underlying assumption made in a theorem proposed by Bandler.