John's ellipsoid and the integral ratio of a log-concave function

We extend the notion of John’s ellipsoid to the setting of integrable log-concave functions. This will allow us to define the integral ratio of a log-concave function, which will extend the notion of volume ratio, and we will find the log-concave function maximizing the integral ratio. A reverse functional affine isoperimetric inequality will be given, written in terms of this integral ratio. This can be viewed as a stability version of the functional affine isoperimetric inequality.Ministerio de Economía y CompetitividadFondo Europeo de Desarrollo RegionalConsejería de Industria, Turismo, Empresa e Innovación (Comunidad Autónoma de la Región de Murcia)Coordenação de aperfeiçoamento de pessoal de nivel superiorInstituto Nacional de Matemática Pura e Aplicad

Implementation of conceptual validation of product mock ups with augmented reality

La implementación de ayudas informáticas en el diseño de productos es prácticamente una demanda en el diseño del siglo XXI, ya que su uso permite un aumento de la calidad y la creatividad de los entregables de un proceso de diseño. Pero esta implementación debe estar guiada por un proceso académico, en el cual se implementen tecnologías y metodologías de trabajo. El presente artículo muestra los resultados de una implementación de técnicas de realidad virtual y aumentada para validar el diseño de productos en cursos de movilidad eléctrica dentro del pregrado en Ingeniería de Diseño de Producto en la Universidad EAFIT.The implementation of computational aids in product design is a demand in the design processes on century XXI, that because they allow an increase in quality and creativity of the deliverables of a design process. But this implementation should be guided to an academic process, where technologies methodologies work along. This article presents the results of an implementation of virtual reality techniques to validate and increased product design courses within the undergraduate electrical mobility in Product Design Engineering at that university

Cálculo del caudal ambiental mediante una metodología holística en la cuenca alta del río Bogotá

Saneamiento de comunidadesEl presente proyecto, mediante un caso de estudio, se aplica la metodología de Caudal Ambiental propuesto por la ANLA en la cuenca alta del río Bogotá y se compara con algunas metodologías adicionales utilizadas para el cálculo del caudal ambiental.INTRODUCCIÓN 1. GENERALIDADES DEL TRABAJO DE GRADO 2. MARCO DE REFERENCIA 3. METODOLOGÍA 4. ANÁLISIS DE RESULTADOS 5. CONCLUSIONES Y RECOMENDANCIONES BIBLIOGRAFÍAEspecializaciónEspecialista en Recursos Hídrico

Performance of random linear coding over multiple error-prone wireless links

In this letter we derive an exact formulation for the performance of Random Linear Coding (RLC) when applied over multiple wireless links. We combine this technique with UDP so as to offer a reliable communication service . We extend a previous result, which only considered one single link, to embrace both multiple sources as well as varying quality of wireless links. We establish the number of excess packets that are required to successfully accomplish the communication and, based on the Bianchi model, we calculate the achieved throughput. We also propose a context-aware probabilistic transmission scheme that leads to a relevant performance gain. We use a thorough simulation-based study over the ns-3 framework to assess the validity of the proposed model and to broaden the corresponding analysis.This work has been supported by the Spanish Government by its funding through the project COSAIF, “Connectivity as a Service: Access for the Internet of the Future” (TEC2012-38754-C02-01)

Five texture zeros and CP violation for the standard model quark mass matrices

ABSTRACT: The phenomenology of the five independent sets of 3 3 quark mass matrices with five texture zeros is carried through in full detail, including predictions for the CP-violation asymmetries. Our study is done without any approximation, first analytically and then numerically

A finite-time consensus algorithm with simple structure for fixed networks

In this paper, a continuous-time consensus algorithm with guaranteed finite-time convergence is proposed. Using homogeneity theory, finite-time consensus is proved for fixed topologies. The proposed algorithm is computationally simpler than other reported finite-time consensus algorithms, which is an important feature in scenarios of energy efficient nodes with limited computing resources such as sensor networks. Additionally, the proposed approach is compared on simulations with existing consensus algorithms, namely, the standard asymptotic consensus algorithm and the finite-time and fixed-time convergent algorithms, showing, in cycle graph topology, better robustness features on the convergence with respect to the network growth with less control effort. Indeed, the convergence time of other previously proposed consensus algorithms grows faster as the network grows than the one herein proposed whereas the control effort of the proposed algorithm is lower

Designing predefined-time differentiators with bounded time-varying gains

There is an increasing interest in designing differentiators, which converge exactly before a prespecified time regardless of the initial conditions, i.e., which are fixed-time convergent with a predefined Upper Bound of their Settling Time (UBST), due to their ability to solve estimation and control problems with time constraints. However, for the class of signals with a known bound of their $(n+1)$-th time derivative, the existing design methodologies are either only available for first-order differentiators, yielding a very conservative UBST, or result in gains that tend to infinity at the convergence time. Here, we introduce a new methodology based on time-varying gains to design arbitrary-order exact differentiators with a predefined UBST. This UBST is a priori set as one parameter of the algorithm. Our approach guarantees that the UBST can be set arbitrarily tight, and we also provide sufficient conditions to obtain exact convergence while maintaining bounded time-varying gains. Additionally, we provide necessary and sufficient conditions such that our approach yields error dynamics with a uniformly Lyapunov stable equilibrium. Our results show how time-varying gains offer a general and flexible methodology to design algorithms with a predefined UBST