Colorful Curvature
نویسنده
چکیده
Nonlinearities provide a neverending challenge to systems and control. We savor linear systems since we have a good understanding of how they behave, and there is much we can do to analyze and predict their performance. As we move away from linearity, we need to scrutinize each nonlinearity that we encounter to assess its benefi t or detriment in terms of what we wish to achieve. The first issue to consider is the way in which the nonlinearity is interconnected with the linear dynamics. For example, consider a cascade interconnection. If the nonlinearity precedes the linear system, then the system is Hammerstein; if it occurs after the linear system, then the system is Wiener. Nonlinear actuation makes a system Hammerstein, while nonlinear sensing makes it Wiener. In both cases the intermediate signal is assumed to be unknown. It seems that Wiener systems are more difficult to deal with than Hammerstein systems for the simple reason that knowing the input to the nonlinearity is more useful than knowing its output. Of course, all systems Colorful Curvature
منابع مشابه
Computational Aspects of the Colorful Carathéodory Theorem
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