Predictive control Terms Links

This paper describes the development of a novel dynamic predictive and optimal control method for the wet end of a papermaking systems. This part of the system plays an important function in the process in terms of its controllability and potential for optimisation. The wet end process is complicated and the control systems are always multivariable and dynamic in nature. Due to the severe interactions between each variable, general physical and chemistry based modelling techniques cannot be established. As such, feed-forward neural networks are selected as a modelling tool so as to build up a number of non-linear models that link all the variables to the concerned quality outputs and process efficiency. 

It is well known that the volume change mechanisms in conducting polymers are complex because the electrical, mechanical, and chemical properties of the material, all of which influence the behavior, are closely coupled [67, 69]. This applies to other kinds of electroactive polymers, especially ionic ones. For precise prediction of the deformation response of the materials, these inextricably linked characteristics should be considered. Such model would be useful for long term motion planning of the machines made of such materials. Simple decoupled models which are proposed in this book are aimed to be utilized for machine design and control. Combination of simple and complex models would help us further understanding of the materials and making use of them for machines. 

The complexity of the phenomenon of adhesion, as well as the diversity of materials capable of adhesive interaction, mean that a whole series of monographs would be required to constitute a comprehensive treatise. The purpose of this paper is more modest. We aim to present simple views on polymer adhesion to readers who are not familiar with this field. We choose to do so on a specific example, namely the adhesion between two cross-linked elastomers (a cross-linked elastomer consists of long, flexible chain-like molecules which are interconnected at various points by cross-links to form a molecular network the polymer medium is locally fluid but the macroscopic flow of the material is prevented by the cross-links). This choice is motivated by a number of reasons (a) the possibility of describing the fracture of the adhesive junction between the two elastomers in terms of a simple model, (b) the existence of controlled experiments that can be compared with the predictions of the model, (c) the possibility of introducing concepts that are of interest for other polymer adhesion problems, and, finally, (d) the fact that adhesion between elastomers is a technologically important field. Several texts on polymer adhesion are avaible (Wu, 1982 Kinloch, 1987 Lee, 1991 Vakula and Pritykin, 1991). A good reference for the results of the last few years is the review article by Brown (1991). 

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