Search results for "temes"
showing 10 items of 75 documents
Las culturas de la emigración española: reflejos audiovisuales de la clase obrera
2019
[spa] El objetivo del presente artículo es estudiar la representación de la emigración española hacia Europa, colocando el acento en su pertenencia a la clase obrera. Por ello, consideraremos films rodados en el contexto franquista, propuestas realizadas al margen de la industria o militantes, películas producidas por los países de acogida o audiovisuales dirigidos por personas que hayan vivido la experiencia de la emigración (primera y segunda generación). Todas estas distintas variables nos permitirán conocer y estudiar la complejidad que entraña abordar este tema y a su vez también analizaremos la relevancia que se concede en estos títulos a la condición obrera. Asimismo, valoraremos la …
Optimal design of complex passive-damping systems for vibration control of large structures: An energy-to-peak approach
2014
Published version of an article in the journal: Abstract and Applied Analysis. Also available from the publisher at: http://dx.doi.org/10.1155/2014/510236 Open Access We present a new design strategy that makes it possible to synthesize decentralized output-feedback controllers by solving two successive optimization problems with linear matrix inequality (LMI) constraints. In the initial LMI optimization problem, two auxiliary elements are computed: a standard state-feedback controller, which can be taken as a reference in the performance assessment, and a matrix that facilitates a proper definition of the main LMI optimization problem. Next, by solving the second optimization problem, the …
Recent Advances in Static Output-Feedback Controller Design with Applications to Vibration Control of Large Structures
2014
Published version of an article in the journal: Modeling, Identification and Control. Also available from the publisher at: http://dx.doi.org/10.4173/mic.2014.3.4 Open Access In this paper, we present a novel two-step strategy for static output-feedback controller design. In the first step, an optimal state-feedback controller is obtained by means of a linear matrix inequality (LMI) formulation. In the second step, a transformation of the LMI variables is used to derive a suitable LMI formulation for the static output-feedback controller. This design strategy can be applied to a wide range of practical problems, including vibration control of large structures, control of oshore wind turbine…
Static output-feedback controller design for vehicle suspensions: an effective two-step computational approach
2014
In this study, a novel two-step methodology is applied in designing static output-feedback controllers for a class of vehicle suspension systems. Following this approach, an effective synthesis of static output-feedback controllers can be carried out by solving two consecutive linear matrix inequality optimisation problems. To illustrate the main features of the proposed design strategy, two different static output-feedback H 8 controllers are designed for a quarter-car suspension system. The first of those controllers uses the suspension deflection and the sprung mass velocity as feedback information, whereas the second one only requires the sprung mass velocity to compute the control acti…
Static output-feedback control for vehicle suspensions: a single-step linear matrix inequality approach
2013
In this paper, a new strategy to design static output-feedback controllers for a class of vehicle suspension systems is presented. A theoretical background on recent advances in output-feedback control is first provided, which makes possible an effective synthesis of static output-feedback controllers by solving a single linear matrix inequality optimization problem. Next, a simplified model of a quarter-car suspension system is proposed, taking the ride comfort, suspension stroke, road holding ability, and control effort as the main performance criteria in the vehicle suspension design. The new approach is then used to design a static output-feedbackH∞controller that only uses the suspensi…
Scaling and data collapse for the mean exit time of asset prices
2005
We study theoretical and empirical aspects of the mean exit time of financial time series. The theoretical modeling is done within the framework of continuous time random walk. We empirically verify that the mean exit time follows a quadratic scaling law and it has associated a pre-factor which is specific to the analyzed stock. We perform a series of statistical tests to determine which kind of correlation are responsible for this specificity. The main contribution is associated with the autocorrelation property of stock returns. We introduce and solve analytically both a two-state and a three-state Markov chain models. The analytical results obtained with the two-state Markov chain model …
The influence of the solvent's mass on the location of the dividing surface for a model Hamiltonian
2019
The Transition State dividing surface is a key concept, not only for the precise calculation of the rate constant of a reaction, but also for the proper prediction of product ratios. The correct location of this surface is defined by the requirement that reactive trajectories do not recross it. In the case of reactions in solution the solvent plays an important role in the location of the dividing surface. In this paper we show with the aid of a model Hamiltonian that the effective mass of the solvent can dramatically change the location of the dividing surface. Keywords: Dynamical systems, Dividing surface, Reactions in solution, 2019 MSC: 00-01, 99-00
Resolution-enhanced optical coherence tomography based on classical intensity interferometry.
2009
We propose a fourth-order interference scheme for optical coherence tomography operating with broadband incoherent (or quasi-incoherent) light. It is shown that using this proposal, an axial resolution improvement by a factor of 2 and a better sensitivity for weakly reflecting samples are obtained than with the standard second-order correlation scheme. From a practical perspective, we suggest the use of broadband Q-switched pulses and performing ultrafast intensity correlation with a nonlinear crystal. The global performance of our proposal is illustrated by means of numerical simulations
Sistemas de información ambiental (bases de datos georreferenciadas y aplicaciones SIG): herramientas para la gestión y control de plagas de importan…
2019
El desarrollo tecnológico combinado en los ámbitos de las ciencias naturales y la informática, además de la fuerte demanda de cartografía digital ambiental en los últimos 50-60 años, han conducido al desarrollo de diversas herramientas de gestión espacial de la información medioambiental. De esta manera, todo tipo de variables ambientales pueden ser cartografiadas y sus elementos por lo tanto tenerlos localizados, lo que permite que a través de estas aplicaciones de gestión de la información puedan ser relacionados entre sí y con otras variables del medio.
Principals instruments utilitzats en psicologia jurídica a través de l’estudi dels articles indexats en la web of science
2017
L’objectiu del present treball és conéixer els principals instruments utilitzats en la Psicologia Jurídica i els temes d’investigació més rellevants a través de l’anàlisi dels articles indexats en les bases de dades de la Web of Science durant i, en concret, de l’any 2014, i que han sigut publicats en revistes incloses en les categories temàtiques Criminology & Penology, Law and Psychology de les bases de dades JCR (SSCI) de l’any 2014. El nombre total d’articles revisats van ser 810. Els resultats revelen que els instruments més emprats són Conflict Tactics Scales, Psychopathy Checklisti Static Risk Matrix. Els trastorns més freqüents en les investigacions van ser el Trastorn per estrés po…