6 resultados para model-based reasoning processes
em Archivo Digital para la Docencia y la Investigación - Repositorio Institucional de la Universidad del País Vasco
Resumo:
Methods for generating a new population are a fundamental component of estimation of distribution algorithms (EDAs). They serve to transfer the information contained in the probabilistic model to the new generated population. In EDAs based on Markov networks, methods for generating new populations usually discard information contained in the model to gain in efficiency. Other methods like Gibbs sampling use information about all interactions in the model but are computationally very costly. In this paper we propose new methods for generating new solutions in EDAs based on Markov networks. We introduce approaches based on inference methods for computing the most probable configurations and model-based template recombination. We show that the application of different variants of inference methods can increase the EDAs’ convergence rate and reduce the number of function evaluations needed to find the optimum of binary and non-binary discrete functions.
Resumo:
This paper presents a vaccination strategy for fighting against the propagation of epidemic diseases. The disease propagation is described by an SEIR (susceptible plus infected plus infectious plus removed populations) epidemic model. The model takes into account the total population amounts as a refrain for the illness transmission since its increase makes the contacts among susceptible and infected more difficult. The vaccination strategy is based on a continuous-time nonlinear control law synthesised via an exact feedback input-output linearization approach. An observer is incorporated into the control scheme to provide online estimates for the susceptible and infected populations in the case when their values are not available from online measurement but they are necessary to implement the control law. The vaccination control is generated based on the information provided by the observer. The control objective is to asymptotically eradicate the infection from the population so that the removed-by-immunity population asymptotically tracks the whole one without precise knowledge of the partial populations. The model positivity, the eradication of the infection under feedback vaccination laws and the stability properties as well as the asymptotic convergence of the estimation errors to zero as time tends to infinity are investigated.
Resumo:
In this work we investigate if a small fraction of quarks and gluons, which escaped hadronization and survived as a uniformly spread perfect fluid, can play the role of both dark matter and dark energy. This fluid, as developed in [1], is characterized by two main parameters: beta, related to the amount of quarks and gluons which act as dark matter; and gamma, acting as the cosmological constant. We explore the feasibility of this model at cosmological scales using data from type Ia Supernovae (SNeIa), Long Gamma-Ray Bursts (LGRB) and direct observational Hubble data. We find that: (i) in general, beta cannot be constrained by SNeIa data nor by LGRB or H(z) data; (ii) gamma can be constrained quite well by all three data sets, contributing with approximate to 78% to the energy matter content; (iii) when a strong prior on (only) baryonic matter is assumed, the two parameters of the model are constrained successfully. (C) 2014 The Authors. Published by Elsevier B.V.
Resumo:
[ES] El presente trabajo ha estudiado la eficacia de la asignatura de Educación Física dentro del Sistema Educativo Español como método de inclusión para el alumnado con Parálisis Cerebral. Hemos realizado la Fundamentación Teórica sobre la Educación Física y la Parálisis Cerebral y hemos explicado la metodología utilizada hasta ahora en las clases (LOCE 2002 y LOMCE 2014) con el objetivo de lograr la integración de estas personas en las clases de E. Física y en la sociedad. Además, hemos llevado a cabo un caso práctico en el que se asistió a una clase de Educación Física con un paralítico cerebral en el Instituto Valle del Ebro (Tudela, Navarra), con el fin de analizar, tanto la clase impartida por el profesor, como la situación que vivía el alumno dentro de la misma. Los resultados de algunas investigaciones avalan que aún queda mucho camino por recorrer en esta área de intervención, Orta Tierra, J.; Badia Corbella, M.; Mayán, Núñez Mª Teresa entre otros. Por último, hemos propuesto el modelo de intervención metodológica por proyectos (procesos) en la EF de la próxima década, con vistas a su posible utilización con alumnos que presenten este trastorno.
Resumo:
This paper analyzes the cyclical properties of a generalized version of Uzawa-Lucas endogenous growth model. We study the dynamic features of different cyclical components of this model characterized by a variety of decomposition methods. The decomposition methods considered can be classified in two groups. On the one hand, we consider three statistical filters: the Hodrick-Prescott filter, the Baxter-King filter and Gonzalo-Granger decomposition. On the other hand, we use four model-based decomposition methods. The latter decomposition procedures share the property that the cyclical components obtained by these methods preserve the log-linear approximation of the Euler-equation restrictions imposed by the agent’s intertemporal optimization problem. The paper shows that both model dynamics and model performance substantially vary across decomposition methods. A parallel exercise is carried out with a standard real business cycle model. The results should help researchers to better understand the performance of Uzawa-Lucas model in relation to standard business cycle models under alternative definitions of the business cycle.
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Documento de trabajo