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Fitness evaluations

It is also true that fitness functions are sometimes augmented in ways that have an influence not only on the final product (i.e., a design with a certain functionality), but also on the manner in which the GA searches the space of all possible designs. [Pg.297]


Representation requires that the designer of a typical evolutionary computation algorithm (EA) formulates one inadaptable blueprint for the solution of some problem, then present the variables of that blueprint in a form that is amenable to manipulation by the genetic operators of the EA. Fitness evaluation, on the other hand, has limited GA in two distinct ways (1) it has limited environmental feedback to the confines of a formula or algorithm, which reflects accurately and exclusively the quality of the complete candidate solution from the perspective of the human designer. In addition, (2) fitness evaluation has proven to be the most computationally costly part of a typical EA. Note that elaborate developmental mappings actually increase that computational cost. However, our interest here lies in the limiting effects of representation. [Pg.324]

The explicit feasibility constraints of (MASTER) are given by the linear first-stage constraints in (9.4.2). In a classical penalty function approach, the explicit feasibility constraints are relaxed while the violation of these constraints is considered by an additional penalty term in the fitness function. However, this method would waste valuable CPU time since the MILP subproblems (SUB) have to be solved also for the fitness evaluation of infeasible individuals. A similar method which does not require the solution of the MILP subproblems for infeasible individuals is the use of a modified objective Junction that separates the objective and the feasibility... [Pg.204]

Probably the most common internal validation method, cross-validation, involves the execution of one or more internal validation procedures (hereby called sub-validations), where each procedure involves the removal of a part of the calibration data, use of the remaining calibration data to build a subset calibration model, and subsequent application of the removed data to the subset calibration model. Unlike the Model fit evaluation method discussed earlier, the same data are not used for model building and model testing for each of the sub-validations. As a result, they can provide more realistic estimates of a model s prediction performance, as well as better assessments of the optimal complexity of a model. [Pg.271]

Van Nimwegen and Crutchfield (1999a) studied the optimum population size to minimize the required number of fitness evaluations E before... [Pg.126]

The discrimination among rival models has to take into account the fact that, in general, when the number of parameters of a model increases, the quality of fit, evaluated by the sum S(a) of squared deviations, increases, but that, at the same time, the size of confidence regions for parameters also increases. Thus, there is, in most cases, a compromise between the wish to lower both the residuals and the confidence intervals for parameters. The simplest way to achieve the discrimination of models consists of comparing their respective experimental error variances. Other methods and examples have been given in refs. 25, 32 and 195—207. [Pg.316]

Molecular orbital calculations were introduced to estimate the active conformations of azole compounds at an enzyme active site. The computed data were discussed referring to the spectroscopic information and utilized for the steric fit evaluation. [Pg.340]

The steric fit evaluation between the low energy conformers of (I) and that of lanosterol was carried out in such a way that the N4 and C14 methyl carbon atoms locate in close proximity. In the case of (II), the C19 methyl carbon of (-)-kaur-16-ene was used for the evaluation. Based on these results, the conformers of (I) and (II) which well overlapped with the natural substrates were selected. [Pg.347]

The Z-isomer (III) is much less fungitoxic than (I) (J 5 ). The steric fit evaluation between (I) and (III) by computer graphics indicates the similarity of three-dimensional structure, as shown in Figure 10. The tert-butyl moiety of (III) occupies the space where the 1, 2,4-triazo1y1 moiety of (I) locates. It is interesting to compare these results with those of the binding assay. The co-ordination of the tert-butyl group to Fe atom of porphyrin moiety of cytochrome... [Pg.347]

Based on these results, the proposed mode of action of uniconazole (ES pure) is illustrated as an example in Figure 11. Although each of the methods used in this study is already known, the combined application of these methods enables to reduce the number of conceivable active conformations and hence the steric fit evaluation can be performed with high accuracy. The remaining problem is how the azole compounds interact with the non-active sites of enzymes. This is surely related to the difference of biological activity between the optical isomers. [Pg.349]

Figure 10 Steric fit evaluation by computer graphics between (I) (---) and its Z-isomer (III) (----). Figure 10 Steric fit evaluation by computer graphics between (I) (---) and its Z-isomer (III) (----).
Another hybrid is described in Klamroth and Miettinen (2007), where an adaptive approximation method (Klamroth et al., 2002) approximating the Pareto optimal set is hybridized with reference point ideas. This means that the approximation is made more accurate only in those parts of the Pareto optimal set that the DM is interested in. Finally, let us mention one more hybrid method where reference points and achievement scalarizing functions are hybridized in EMO, see Thiele et al. (2007). On a general level, the idea is the same as in the previous hybrid but here the achievement scalarizing function is incorporated in the fitness evaluation and the interactive algorithm is different. Other ideas of handling preferences in EMO are surveyed in Coello (2000). [Pg.170]

TABLE 4 Fit Evaluation of Small-Angle X-Ray Scattering Experiments on Systems 3 and 4... [Pg.99]

Additional examinations that are independent of medical surveillance will be required. These include fitness evaluations for personal protective equipment and evaluation of a potential worker s ability to meet the functional requirements of the job. [Pg.402]


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See also in sourсe #XX -- [ Pg.297 , Pg.305 ]

See also in sourсe #XX -- [ Pg.267 ]




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