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Numerical optimization multidimensional

At this point it may seem as though we can conclude our discussion of optimization methods since we have defined an approach (Newton s method) that will rapidly converge to optimal solutions of multidimensional problems. Unfortunately, Newton s method simply cannot be applied to the DFT problem we set ourselves at the beginning of this section To apply Newton s method to minimize the total energy of a set of atoms in a supercell, E(x), requires calculating the matrix of second derivatives of the form SP E/dxi dxj. Unfortunately, it is very difficult to directly evaluate second derivatives of energy within plane-wave DFT, and most codes do not attempt to perform these calculations. The problem here is not just that Newton s method is numerically inefficient—it just is not practically feasible to evaluate the functions we need to use this method. As a result, we have to look for other approaches to minimize E(x). We will briefly discuss the two numerical methods that are most commonly used for this problem quasi-Newton and... [Pg.70]

M. Ihlow, L. Mori, Unsteady multidimensional liquid distribution in fluidized bed spray granulation numerical solution and optimization aspects, Proceedings, 3rd European Congress of Chemical Engineering ECCE-3, Nuremberg, June 26-28,... [Pg.530]

As this approach deals with a set of classical trajectories, its numerical cost remains reasonable for multidimensional systems. Contrary to the classical approach, which controls only the averaged classical quantities, the present semiclassical method can control the quantum motion itself. This makes it possible to reproduce almost all quantum effects at a computational cost that does not grow too rapidly as the dimensionality of the system increases. The new approach therefore combines the advantages of the quantum and classical formulations of the optimal control theory. [Pg.121]

M. L. Lee, L. Blomberg, K. Grob and his family members, G. Schomburg and their colleagues, and many, many others too numerous to mention here. Attention has now shifted to such areas as silphenylene(arylene) phases for GCMS, MS-grade phases, stationary-phase selectivity tuned or optimized for specific applications, multidimensional chromatographic techniques, and immobilization of chiral stationary phases, which are discussed in Section 3.11.6. [Pg.162]

It is clear from the literature that operator workload is a complex area. We have seen that mental workload is a multidimensional concept impacted by numerous factors, so much so that designing systems with the aim of optimizing the workload levels is... [Pg.141]


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Multidimensional optimization

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