Complementary first and second derivative methods for ansatz optimization in variational Monte Carlo

This Perspective contrasts first and second derivative methods in variational Monte Carlo and presents a hybrid optimization approach that combines their advantages.

SPECTRAL INDICES APPLICATION IN THE DETERMINATION OF CROSSBRED LAMBS SLAUGHTER INDICATORS

The report describes the data used for slaughter indicators of crossbred lambs. A method is presented of converting color components to spectral characteristics and their second derivative. Methods of selection of informative wavelengths are used by ABC analysis, using an Euclidean distance between the values of reflection at these lengths. The method used for determining spectral indices is presented. The differences in the Euclidean distances between the spectral indexes have been found to show a regularity similar to that of the water absorption coefficient and the tenderness of meat. The proposed spectral indexes will be used in laboratory conditions for the determination of physico-chemical indicators of crossbreed lambs.

Second derivative Runge-Kutta collocation methods based on Lobatto nodes for stiff systems

Second derivative Runge-Kutta collocation methods for the numerical solution of sti system of rst order initial value problems in ordinary dierential equations are derived and studied. The inclusion of the second derivative terms enabled us to derive a set of methods which are convergent with large regions of absolute stability. Although the implementation of the methods remains iterative in a precisely dened way, the advantage gained makes them suitable for solving sti system of equations with large Lipschitz constants. The derived methods are illustrated by the applications to some test problems of sti system found in the literature and the numerical results obtained conrm the potential of the second derivative methods.