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Model Predictive Controller for piecewise affine system
2005 IFAC 16th Triennial World Congress, Prague, Czech RepublicThis paper presents a hybrid procedure to solve Model Predictive Controller (MPC) for Piecewise Affine System (PWA) The approach presented here belong to the class of Branch and Bound (B&B) methods. The procedure uses the concepts of reachable set combined to the specific B&B methods, in order to reduce the number of Quadratic Problems (QP) needed to be solved by the optimization algorithm
Spin and angular momentum in the nucleon
Using the covariant spectator theory (CST), we present the results of a
valence quark-diquark model calculation of the nucleon structure function f(x)
measured in unpolarized deep inelastic scattering (DIS), and the structure
functions g1(x) and g2(x) measured in DIS using polarized beams and targets.
Parameters of the wave functions are adjusted to fit all the data. The fit
fixes both the shape of the wave functions and the relative strength of each
component. Two solutions are found that fit f(x) and g1(x), but only one of
these gives a good description of g2(x). This fit requires the nucleon CST wave
functions contain a large D-wave component (about 35%) and a small P-wave
component (about 0.6%). The significance of these results is discussed.Comment: 27 pages; 13 figure
Description of nuclear systems with a self-consistent configuration-mixing approach. I: Theory, algorithm, and application to the C test nucleus
Although self-consistent multi-configuration methods have been used for
decades to address the description of atomic and molecular many-body systems,
only a few trials have been made in the context of nuclear structure. This work
aims at the development of such an approach to describe in a unified way
various types of correlations in nuclei, in a self-consistent manner where the
mean-field is improved as correlations are introduced. The goal is to reconcile
the usually set apart Shell-Model and Self-Consistent Mean-Field methods. This
approach is referred as "variational multiparticle-multihole configuration
mixing method". It is based on a double variational principle which yields a
set of two coupled equations that determine at the same time the expansion
coefficients of the many-body wave function and the single particle states. The
formalism is derived and discussed in a general context, starting from a
three-body Hamiltonian. Links to existing many-body techniques such as the
formalism of Green's functions are established. First applications are done
using the two-body D1S Gogny effective force. The numerical procedure is tested
on the C nucleus in order to study the convergence features of the
algorithm in different contexts. Ground state properties as well as
single-particle quantities are analyzed, and the description of the first
state is examined. This study allows to validate our numerical algorithm and
leads to encouraging results. In order to test the method further, we will
realize in the second article of this series, a systematic description of more
nuclei and observables obtained by applying the newly-developed numerical
procedure with the same Gogny force. As raised in the present work,
applications of the variational multiparticle-multihole configuration mixing
method will however ultimately require the use of an extended and more
constrained Gogny force.Comment: 22 pages, 18 figures, accepted for publication in Phys. Rev. C. v2:
minor corrections and references adde
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