Search results for "temes"
showing 10 items of 75 documents
A linear matrix inequality approach to robust fault detection filter design of linear systems with mixed time-varying delays and nonlinear perturbati…
2010
Accepted version of an article in the journal: Journal of the Franklin Institute-Engineering and Applied Mathematics. The definitive version can be found on Sciverse: http://dx.doi.org/10.1016/j.jfranklin.2010.03.004 In this paper, the problem of robust fault detection filter (RFDF) design for a class of linear systems with some nonlinear perturbations and mixed neutral and discrete time-varying delays is investigated. By using a descriptor technique, Lyapunov-Krasovskii functional and a suitable change of variables, new required sufficient conditions are established in terms of delay-dependent linear matrix inequalities (LMIs) to synthesize the residual generation scheme. Based on the Luen…
Structural Vibration Control for a Class of Connected Multistructure Mechanical Systems
2012
Published version of an article from the journal: Mathematical Problems in Engineering. Also available from the publisher:http://dx.doi.org/10.1155/2012/942910 A mathematical model to compute the overall vibrational response of connected multistructure mechanical systems is presented. Using the proposed model, structural vibration control strategies for seismic protection of multibuilding systems can be efficiently designed. Particular attention is paid to the design of control configurations that combine passive interbuilding dampers with local feedback control systems implemented in the buildings. These hybrid active-passive control strategies possess the good properties of passive contro…
Discrete-time multioverlapping controller design for structural vibration control of tall buildings under seismic excitation
2012
Published version of an article from the journal: Mathematical Problems in Engineering. Also available from the publisher:http://dx.doi.org/10.1155/2012/636878 In this paper, a computationally effective strategy to obtain multioverlapping controllers via the Inclusion Principle is applied to design discrete-time state-feedback multioverlapping LQR con- trollers for seismic protection of tall buildings. To compute the corresponding control actions, the proposed semidecentralized controllers only require state information from neighboring stories. This particular configuration of information exchange allows introducing a dramatic reduction in the transmission range required for a wireless imp…
Frequency domain control based on quantitative feedback theory for vibration suppression in structures equipped with magnetorheological dampers
2009
This is an author-created, un-copyedited version of an article accepted for publication in Smart Materials and Structures. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The definitive publisher authenticated version is available online at http://dx.doi.org/10.1088/0964-1726/18/9/095041 This paper addresses the problem of designing quantitative feedback theory (QFT) based controllers for the vibration reduction in a structure equipped with an MR damper. In this way, the controller is designed in the frequency domain and the natural frequencies of the structure can be directly accounted for in the process. T…
Influència de la curvatura del conducte radicular i del moviment en la fatiga cíclica dels instruments de sistemes de llima única
2015
L’objectiu de l’estudi ha sigut avaluar la resistència a la fatiga cíclica de quatres sistemes de llima única en conductes corbats, estudiar la influència del moviment i de l’àrea de la secció transversal. Metodologia. S’utilitzaren un total de 240 llimes noves de 4 sistemes de llima única amb un diàmetre a la punta de 0,25mm: 60 llimes WaveOne Primary (Densply-Maillefer), 60 llimes Reciproc R25 (VDW), 60 llimes OneShape (Micro-Mega) i 60 llimes F360 #25 (Komet Brasseler); que foren dividides de manera aleatòria en 24 grups (ni=10). Prèviament a l’estudi tots els instruments van ser inspeccionats amb un lupa estereomicroscòpica de 16 augments, per a anàlisi morfològic i per descartar qualse…
Optimal passive-damping design using a decentralized velocity-feedback H-infinity approach
2012
In this work, a new strategy to design passive energy dissipation systems for vibration control of large structures is presented. The method is based on the equivalence between passive damping systems and fully decentralized static velocity-feedback controllers. This equivalence allows to take advantage of recent developments in static output-feedback control design to formulate the passive-damping design as a single optimization problem with Linear Matrix Inequality constraints. To illustrate the application of the proposed methodology, a passive damping system is designed for the seismic protection of a five-story building with excellent results. Peer Reviewed
Effect of production system on sensorial characteristics of PDO Cantal cheese
2004
National audience
Diversity, ecology, distribution and biogeography of Diplura
2021
1. Diplura is the sister group to insects and one of the three basal hexapod groups with unique entognathan mouthparts. The order is divided into 10 families, which include 1008 species in 141 genera, with a high proportion of monotypic genera. They are ubiquitous in soils and subsurface terrestrial habitats, as well as have an important role in overall biogeochemical cycles. 2. We present the first comprehensive review of the global biodiversity and ecology of Diplura. We highlight four aspects of this basal hexapod group: diversity in morpho logical body plans and sizes; ecology in terrestrial environments from soil to caves; food preference and trophic levels, and their biogeographical a…
Análisis y valoración de los sistemas de evaluación de suelos en España. Evolución, tendencias actuales y perspectivas futuras
1997
23 páginas, 5 cuadros.
Preguntas de comprensión audiovisual sobreimpresas: propuesta para el aprendizaje de segundas lenguas
2018
Las actividades de comprensión audiovisual son complejas, especialmente en una segunda lengua. Por un lado, existe un conflicto de atención visual entre ver un vídeo y realizar una tarea escrita simultáneamente. Por otro lado, prestar atención a la imagen, al audio, y a la actividad al mismo tiempo puede saturar la memoria de trabajo. En este artículo se describe una propuesta innovadora que puede ayudar a limitar esta complejidad en las áreas de la enseñanza y la evaluación de segundas lenguas: el uso de preguntas de comprensión audiovisual integradas en la imagen del vídeo en forma de subtítulos y sincronizadas con los fragmentos relevantes. La propuesta es el resultado de una investigaci…