Search results for "Sistemes"
showing 10 items of 69 documents
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.
La «innovación escondida» de las pymes industriales en el capitalismo español. Gestión, estrategias y repertorios de prácticas innovadoras en pymes m…
2019
Las pymes industriales dinámicas e innovadoras son una de las bases de prosperidad colectiva en algunos países y regiones europeas. Desde una sociología multinivel que integra los niveles micro (empresarial-organizativo), meso (regional-local y sectorial) y macro (capitalismo estatal-nacional) dentro del sistema de redes-cadenas de producción del capitalismo global, el artículo analiza la actividad innovadora de las pymes industriales, la cual se puede denominar innovación escondida al no aparecer en los indicadores convencionales de innovación. En base a 22 entrevistas semiestructuradas a directivos de pymes manufactureras de Cataluña, se aplica la Teoría Fundamentada para construir catego…
Educational Impact Evaluation of Professional Development of In-Service Teachers: The Case of the Dialogic Pedagogical Gatherings at Valencia “On Gia…
2021
There is a broad consensus on the impact of teacher quality on students’ outcomes. However, the debate on how to evaluate the impact of teacher training on student improvement remains open. The evaluation of the impact of in-service teacher training, organized in a network for different schools, has been analyzed very little to date. Our research displays an innovative approach in this regard, through an In-Service Professional Development Program based upon scientific evidence and dialogic principles: The Pedagogical Gatherings “On Giant’s Shoulders”. We conducted a multilevel communicative study to analyze its impact upon students’ achievement and schools’ outcomes whose teachers taking p…
Información geográfica y riesgos naturales
2001
Información geográfica y riesgos naturales
Siose Valencia 2005: resultados, aplicaciones y comparación con Corine
2011
SIOSE, Spanish acronym standing for Land Cover and Use Information System of Spain, is the most detailed Geographic Information System ever created in Spain about land cover and land use. This GIS gives objective information, photo-interpreted from aerial and satellite imagery, describing the different land covers and land uses. Since SIOSE gathers a big deal of information (more than 157.000 different polygons just in the Land of Valencia), the quantity of possible researches coming from it is huge and ranging from environmental and biodiversity subjects to agricultural or urban areas topics. These possible researches would be especially appropriate on a local level, since SIOSE has a very…