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Mulero-Martinez J.I.,Technical University of Cartagena
IEEE Transactions on Neural Networks and Learning Systems | Year: 2012

A new Gaussian radial basis function static neurocontroller is presented for stable adaptive tracking control. This is a two-stage controller acting in a supervisory fashion by means of a switch logic and allowing arbitration between a neural network (NN) and a robust proportional-derivative controller. The structure is intended to reduce the effects of the curse of dimensionality in multidimensional systems by fully exploiting the mechanical properties of the robot manipulator. A new factorization of the Coriolis/centripetal matrix is used, leading to an NN model that is much smaller than the dynamic ones. By resorting to the extended multivariate Shannon theorem and the computation of the effective bandwidth of the revolute robot manipulators, the network parameters are tuned. Stability and convergence properties are analyzed. This provides the assurance of reliability and effectiveness to make such controller viable. A robot manipulator with two degrees of freedom is employed to study the adaptive features of the neural control algorithm. Finally, the effectiveness of the proposed method is compared to the nonadaptive case. © 2012 IEEE. Source


Otero T.F.,Technical University of Cartagena
Polymer Reviews | Year: 2013

Electro-generations of conducting polymers are fast processes through a complex mechanism of parallel reactions giving mixed materials. The films are three-dimensional electrochemical reactors: reactive macromolecules, ions, and solvent. The film composition and its related properties reviewed here change by oxidation/reduction along several orders of magnitude under control. One reaction shifts different properties (multifunctionality). In one device several reaction driven tools, actuators and sensor, work simultaneously (full integration). The activation energy, the coefficient, and the reaction order shift with the initial state of packing conformations. Trapping charges and conformational energetic states constitute new multivalent chemo-conformational memories, close to brain memory. © 2013 Copyright Taylor and Francis Group, LLC. Source


Lopez-Nicolas A.,Technical University of Cartagena
Tobacco control | Year: 2013

The Spanish government has strengthened tobacco control policies since 2005, including changes in tobacco taxes. Because these changes have targeted cigarettes mainly, the tobacco industry has marketed cheaper alternative tobacco products, offering smokers the possibility to downtrade. This paper traces the evolution of patterns of demand for cigarettes and other tobacco products in Spain over the period 2005-2011 in order to assess the impact of such tax loopholes. The authors use data on tobacco products prices and sales as well as changes in the structure and levels of tobacco taxes to relate tax changes to price changes and subsequent market share changes. Tax reforms have lifted the bottom end of the cigarette price distribution, but the industry has been successful in marketing fine-cut tobacco at cheap prices. There have been partial attempts to correct this asymmetric tax treatment, but these have not avoided a remarkable increase in the market share of fine-cut tobacco. The absence of a minimum tax on quantity for the rest of tobacco products allows the industry to place them as potential future downtrading vehicles. In order to address public health objectives, tax policies should aim to equalise the cost of smoking across different tobacco products. Otherwise the tobacco industry can exploit tax loopholes to market cheap alternatives to cigarettes. This requires all tobacco products to bear a minimum tax on quantity, whose levels need to be adjusted in order to reflect the equivalence between different forms of smoking. Source


Otero T.F.,Technical University of Cartagena
Journal of Materials Chemistry B | Year: 2013

Life is supported by cellular reactions driving conformational, folding and unfolding macromolecular movements with ionic and aqueous exchange. Here we review the state of the art of the electrochemistry of conducting polymers as elemental material models of biological reactive gels. The different experimental methodologies allowing identification and quantification of the reaction induced molecular (conformation) and macroscopic (relaxation, swelling, shrinking and compaction) structural changes are reviewed. Similar structural effects from other materials and systems, artificial or biological, are presented. Some reaction induced properties and devices mimicking biological functions and organs are described: sensing and tactile artificial muscles, smart membranes, artificial glands or artificial chemical synapses. The new structural chemical kinetics opens the way to modelling and predicting health issues linked to reactive folding or misfolding processes, and to advancing the knowledge of brain molecular mechanisms such as memory. Chemo-electronic conformational memories and dual sensing-actuating, zoomorphic and anthropomorphic gel tools and robots are envisaged. This journal is © 2013 The Royal Society of Chemistry. Source


Grant
Agency: Cordis | Branch: H2020 | Program: MSCA-ITN-ETN | Phase: MSCA-ITN-2014-ETN | Award Amount: 3.30M | Year: 2015

Electroactive polymers (EAP) consist of materials capable of changing dimensions and/or shape in response to electrical stimuli. Most EAPs are also capable of generating electrical energy in response to applied mechanical forces. These polymeric materials exhibit properties well beyond what conventional metal or plastic-based actuators can offer, including very high mechanical flexibility (can be stretched to twice their initial size), low density, a high grade of processability, scalability, microfabrication readiness and, in most cases, low cost. Micro-EAPs enable a new broad range of applications for which large strains and forces are desirable, and for which built-in intelligence is necessary. The main objective of the project will be the improvement of the career perspectives (in academia and in industry) of young researchers by training them at the forefront of research in the field of smart soft systems made of EAP microactuators for advanced miniaturized devices. The overall objective for the scientific programme is research and development of EAP materials and their integration for industrial applications. Special attention will be devoted to the development of microactuators. The field of smart materials is growing extremely fast. Materials whose stiffness and shape can be controlled, and that are capable of sensing their shape allow new classes of compliant complex systems. Through the MICACT programme, we hope to ensure that European researchers keep their leading role in this blossoming field, and to help them transition to industrial positions.

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