Non-integrability of the Armbruster-Guckenheimer-Kim quartic Hamiltonian through Morales-Ramis theory

We show the non-integrability of the three-parameter Armburster-Guckenheimer-Kim quartic Hamiltonian using Morales-Ramis theory, with the exception of the three already known integrable cases. We use Poincar\'e sections to illustrate the breakdown of regular motion for some parameter values.Comment: Accepted for publication in SIAM Journal on Applied Dynamical Systems. Adapted version for arxiv with 19 pages and 11 figure

Dual mode nonlinear model based predictive control with guaranteed stability

Resumen En este artículo se propone un Control Predictivo Basado en un Modelo no Lineal (NMPC) pero que opera por modo dual y con estabilidad garantizada. El modo dual se logra usando un controlador PI dentro de la región terminal del NMPC. Para el cálculo de la región terminal (Ω) y del dominio de atracción se usa la teoría de conjuntos y un algoritmo aleatorizado tipo Montecarlo. En la estrategia de conmutación NMPC al PI se restringen los elementos finales de control suavizando la conmutación. El NMPC por Modo Dual propuesto se implementa en simulación en un Reactor Continuamente Agitado, comparando su desempeño con el de un NMPC multivariable convencional y dos controladores PI. Se concluye que el NMPC por modo dual propuesto es la estrategia de control que además de tener estabilidad garantizada, presenta mejor desempeño. Abstract: This paper proposes a Nonlinear Model based Predictive Control (NMPC), with guaranteed stability using a dual mode Model based Predictive Control approach with a PI controller inside a terminal region. Within the formulation of this control strategy, a terminal region (Ω) and an attraction domain are calculated using invariant sets theory and a randomized Montecarlo type algorithm. In addition, this proposal is complemented with a commutation strategy to constrain final control elements smoothing controllers commutation. This Dual Mode NMPC multivariable control is implemented by simulation over a Continuous Stirred Reactor Tank and comparing Dual Mode NMPC with a conventional NMPC multivariable and with two PI controllers. Finally, this article concludes that the NMPC for dual mode is the control strategy that in addition to having stability guaranteed, presents a better performance

Ejection–collision orbits in two degrees of freedom problems in celestial mechanics

The version of record is available online at: http://dx.doi.org/10.1007/s00332-021-09721-5In a general setting of a Hamiltonian system with two degrees of freedom and assuming some properties for the undergoing potential, we study the dynamics close and tending to a singularity of the system which in models of N-body problems corresponds to total collision. We restrict to potentials that exhibit two more singularities that can be regarded as two kind of partial collisions when not all the bodies are involved. Regularizing the singularities, the total collision transforms into a 2-dimensional invariant manifold. The goal of this paper is to prove the existence of different types of ejection–collision orbits, that is, orbits that start and end at total collision. Such orbits are regarded as heteroclinic connections between two equilibrium points and are mainly characterized by the partial collisions that the trajectories find on their way. The proof of their existence is based on the transversality of 2-dimensional invariant manifolds and on the behavior of the dynamics on the total collision manifold; both of them are thoroughly described.Peer ReviewedPostprint (author's final draft

Use and effectiveness of fly goalkeepers in european futsal

Using a fly goalkeeper (FG) is one of futsal´s most specific offensive strategy and gives leverage over the opponent to change the game''s final result. This study will analyze the goals obtained from the use of a FG and relate them to the score momentum variable and others in order to offer a better understanding and to establish if there are differences between main European futsal leagues. Sample made from all offensive situations that lead to a goal while using FG scheme (n=673) during 2014-2015 Spanish, Russian and Italian pro futsal leagues. Observational, nomothetic and multidimensional study. Statistical analysis using the SPSS vr 22 for inferential and descriptive statistics. Chi-square relation for cathegorical variables and Spearman''s Rho to establish non parametrical bi-varial correlations for ordinary variables, establishing significant differences p <0.05. FG strategy obtains 15.33% of the total goals. The league''s behaviour very similar, except in the Italian league, which scores more goals with their attack than against its defence, making differences between goals scored as local and visitor both in attack and defence

Neumonía trombopenia y afectación hepática en un caso de fiebre Q aguda

PneumoniaFebr

A Vector Non-abelian Chern-Simons Duality

Abelian Chern-Simons gauge theory is known to possess a `$S$-self-dual' action where its coupling constant $k$ is inverted {\it i.e.} $k \leftrightarrow {1 \over k}$. Here a vector non-abelian duality is found in the pure non-abelian Chern-Simons action at the classical level. The dimensional reduction of the dual Chern-Simons action to two-dimensions constitutes a dual Wess-Zumino-Witten action already given in the literature.Comment: 14+1 pages, LaTeX file, no figures, version to appear in Phys. Rev

RILEM TC 277-LHS REPORT: A review on the mechanisms of setting and hardening of lime-based binding systems

The main objective of RILEM TC LHS-277 “Specifications for testing and evaluation of lime-based repair materials for historic Structures” is the revision, adaption and, when necessary proposal, of the test methods to accurately study lime-based binding systems and mixtures, such as mortars and grouts. The empiric use of the lime-based composites and the predominant employ of cement in the field of Civil Engineering have led to the widespread application of test methods developed for cement-based composites to test the former. However, the clear differences in composition and performance between modern cement binders and lime-based materials would advise to explore specific test methods for the latter. To undertake this task the previous knowledge on the mechanisms of setting and hardening of these binders must be revised, arranged and synthesized. Processes such as drying, carbonation, hydration and pozzolanic reaction may occur during the setting and hardening of lime-based mortars and competition between them cannot be underestimated. With the aim of underpinning the revision and proposal of test methods for lime-based systems, this review paper reports a comprehensive study of the mechanisms of setting and hardening of these binders, considering the variability of the composition, which includes pure air lime as well as lime with hydraulic properties, lime-cement and lime-pozzolan systems.authorsversionpublishe

Solvable simulation of a double-well problem in PT symmetric quantum mechanics

Within quantum mechanics which works with parity-pseudo-Hermitian Hamiltonians we study the tunneling in a symmetric double well formed by two delta functions with complex conjugate strengths. The model is exactly solvable and exhibits several interesting features. Besides an amazingly robust absence of any PT symmetry breaking, we observe a quasi-degeneracy of the levels which occurs all over the energy range including the high-energy domain. This pattern is interpreted as a manifestation of certain "quantum beats".Comment: 12 pages incl. 7 figure