Multi-tier structure

We proposed a method for deriving nonlinear low-dimensional models for the dynamics in each time scale. Subsequently, we proposed a hierarchical controller design framework that takes advantage of the time-scale multiplicity, and relies on a multi-tiered structure of coordinated decentralized and supervisory controllers in order to address distributed and process-level control objectives. 

Two three-tier networks are shown in Fig. 4.3. In the simplest form of a multi-tier network, a single company is connected to one other company at the next downstream tier in a chain, and it is known as the multi-tier dyadic network or a tree-structure. 

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