Design criteria perspective

From polarization curves of the type shown in case 3, three important parameters can be determined ECOSI, Ebth and In the literature there exists a nearly infinite number of variations of nomenclature, many of which are shown in Table 2. The interpretation of cyclic polarization curves has been and continues to be a subject of great controversy. The classic interpretation of case 3 would be that the potential of a material must exceed EM for new pits (or localized corrosion sites) to nucleate, but that at potentials between EM and En existing pits can propagate. At potentials below En all localized corrosion sites repassivate. Thus, from a design or material selection perspective, a material will perform well if its Econ is kept below This criterion can be met by environment... 

From a practical perspective, the design selection problem amounts to finding the best design matrix D such that the design is optimal with respect do a criterion based on a model /. Thus, the design matrix D, the model /, and the criterion that depends on the model matrix X are three key elements that must be considered. There are several important issues concerning the relationships among these three elements. 

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