Some new results on the self-dual [120,60,24] code

The existence of an extremal self-dual binary linear code of length 120 is a long-standing open problem. We continue the investigation of its automorphism group, proving that automorphisms of order 30 and 57 cannot occur. Supposing the involutions acting fixed point freely, we show that also automorphisms of order 8 cannot occur and the automorphism group is of order at most 120, with further restrictions. Finally, we present some necessary conditions for the existence of the code, based on shadow and design theory.Comment: 23 pages, 6 tables, to appear in Finite Fields and Their Application

Random and stochastic disturbances on the input flow in chemostat models with wall growth

In this paper, we analyze a chemostat model with wall growth where the input flow is perturbed by two different stochastic processes: the well-known standard Wiener process, which leads into several draw- backs from the biological point of view, and a suitable Ornstein- Uhlenbeck process depending on some parameters which allow us to control the noise to be bounded inside some interval that can be fixed previously by practitioners. Thanks to this last approach, which has already proved to be very realistic when modeling other simplest chemostat models, it will be possible to prove the persistence and coexistence of the species in the model without needing the theory of random dynamical systems and pullback attractors needed when dealing with the Wiener process. This is an advantage since the theoretical framework in this paper is much less complicated and provides us much more information than the other

Modeling and analysis of random and stochastic input flows in the chemostat model

In this paper we study a new way to model noisy input flows in the chemostat model, based on the Ornstein-Uhlenbeck process. We introduce a parameter β as drift in the Langevin equation, that allows to bridge a gap between a pure Wiener process, which is a common way to model random disturbances, and no noise at all. The value of the parameter β is related to the amplitude of the deviations observed on the realizations. We show that this modeling approach is well suited to represent noise on an input variable that has to take non-negative values for almost any time.European Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER)Ministerio de Economía y Competitividad (MINECO). EspañaJunta de Andalucí

Studying the long time dynamics of fermentation models: production of dry and sweet wine

In this talk we will consider two classical mathematical models of wine fermentation. The first model will describe the wine-making process that is used to produce dry wine. The second model will be obtained by introducing a term in the equation of the dynamics of the yeast. Thanks to this change it will be possible to inhibit the fermentation of the sugar and as a consequence a sweet wine will be obtained. We will first prove the existence, uniqueness, positiveness and boundedness of solutions for both models. Then we will pass to analyze the long-time dynamics. For the second model we will also provide estimates for the concentration of ethanol, nitrogen and sugar at the end of the process. Moreover, several numerical simulations will be provided to support the theoretical results

El problema de la corrupción como factor influyente en la democracia y la pérdida de legitimidad en instituciones públicas, 2022

La presente investigación recae como objetivo general: Analizar la corrupción como factor influyente en la democracia y la pérdida de legitimidad en instituciones públicas, donde su edificación metodológica está basada por un enfoque cualitativo, de tipo básico, de diseño fenomenológico, teniendo 8 participantes entre fiscales anticorrupción y abogados litigantes con conocimiento en penal y procesal penal, en tal sentido es importante emplear como instrumento la guía de entrevistas, la misma que estuvo formulada por 8 preguntas, teniendo como técnica la entrevista, realizando la transcripción de las preguntas de los participantes para ser contrastados con los resultados obtenidos. Según los hallazgos encontrados, se concluye que, en la comisión de delitos por funcionarios públicos, que perjudica rotundamente la administración pública, los actos de corrupción afectan directamente con el desarrollo y crecimiento de la democracia ante la sociedad, la corrupción degrada y destruye la institucionalidad del aparato estatal perdiendo credibilidad y legitimidad en la Institución Pública, en tal sentido la creación de herramientas legales es fundamental en la lucha contra la corrupción y la creación de políticas públicas anticorrupción con el fin de frenar el avance de este flagelo