Environmental model design procedure

In this chapter, the design of a control scheme for an entire plant will be discussed. On the basis of the relationship between process outputs and inputs, the control scheme will be developed. The first part of the procedure is similar to the procedure for the development of an environmental model, which is identifying the inputs and outputs of the process. Measurement problems and costs of the correcting devices, however, should now also be taken into consideration. The result of this procedure is a table with interactions, in which the relationships between the manipulated and controlled variables is shown. The static relationship determines the power of control the dynamic relationship determines the speed of control. The design procedure is illustrated by an example. Subsequently, methods for optimization and extension of the control scheme are discussed. 

The next sequence of steps (see Table 33.1) can be used as a design procedure, or as a checkhst afterwards if one prefers a more intuitive approach to control system design. The checkhst is more or less similar to the checkhst for the development of an environmental model (Table 3.1). 

The precautionary approach (PA) is an important element of environmental law that is used to address a potential risk whether or not that risk can be demonstrated or its consequences identified. The static use of a sole, generally accepted definition of the PA is extremely difficult, since this cannot meet the multitude of needs in important legislative tools introduced in many conventions designed to protect biodiversity. The way out will be a more discursive model, a model that allows for adaptation to specific conditions and which enforces solution-oriented procedures. 

Progressive acclimation to experimental procedures is usually observed in animal models, and haemodynamic parameters are most sensitive to such environmental interferences. When selecting the optimal study design, this progressive change in baseline conditions needs to be considered. In this context, a dose... 

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