The complexity of many technical applications and production processes is continuously increasing, due to growth in the technological possibilities of the produced goods. For biological processes, which are inherently very complex to begin with, complexity has quite different facets, which find their expression, for example, in the linkage of numerous subprocesses, in nonlinear system dynamics, and in combinations of the two.
Moreover, in many cases, the descriptions of the processes and systems are plagued with significant uncertainties. In technical systems, these result from uncertainties regarding the parameters of integrated components and their time-dependent variability during operations, as well as disturbances originating in the external process environment. In biological systems, the natural fluctuations and variability typical of living systems mean that these uncertainties often play an even more important role. Therefore, when developing new medical compounds or devices, or when designing and controlling bioreactors, for example, it is imperative to take them into account.