Optimized adaptive control on dual buoyancy system for application in underwater gliders

Peer Reviewe

Diseño y fabricación de los álabes de un micro-aerogenerador de baja potencia

El proyecto consiste en estudiar los aspectos que influyen en el diseño de un alabe de un micro-aerogenerador, para posteriormente poder diseñar y fabricar el alabe y que este cumpla unas prestaciones determinadas y óptimas para su instalación en un micro-aerogenerador completo. La principal finalidad del documento es poder explicar el proceso de obtención de un alabe de un micro-aerogenerador desde su fase de diseño, pasando por la fase de fabricación. Esta documentación permitirá que se optimicen mejor los perfiles de este tipo de aerogeneradores y así obtener un mejor rendimiento en la conversión de la energía del viento a energía transformada por los alabes

Anàlisi del bloc de fonaments individuals per demarcació (fid) corresponent a la defensa de l'espai per la posició dels laterals en el futbol: comparació entre categories amateur i semi-professional

Curs 2013-2014L’objectiu d’aquest estudi va ser analitzar un element del component tàctic com a factor determinant en el rendiment del futbol, és a dir, comprovar si hi ha diferències en l’execució del bloc de Fonaments Individuals per Demarcació (FID) corresponent a la defensa de l’espai per la posició dels laterals en el futbol, entre les categories amateur i semi-professional. Es van enregistrar un total de 18 partits, on 9 dels quals feien referència a l’equip de l’Arbúcies Club de Futbol i la resta a l’equip de la Unió Esportiva Llagostera. Les variables estudiades van ser les següents: cobertures al central que defensa al possessor de la pilota, evitar passades interiors que guanyin l’esquena, defensa individual dels jugadors que intenten passar per l’esquena del segon central (entrar-sortir) i eliminar l’espai de desmarcada en profunditat, mantenint la línia amb el central. Per analitzar-les es va utilitzar el programa Longomatch i el Excel on hi vam configurar un instrument d’avaluació. Els principals resultats del treball van ser que l’equip de la Unió Esportiva Llagostera va fer menys errors en l’execució dels FID, tot i que va seguir tenint errors en el compliment d’aquests fonaments.The aim of this study was to analyze an item of the tactical component as a determining factor in the performance of football, that is, checking If there are differences in the block execution of Individual Basis by Position (IBP) corresponding to the space defense for the full backs between the amateur category and the semi-professional category. We recorded 18 matches, of whom 9 were of the Arbúcies Club de Fubol and the rest were of the Unió Esportiva Llagostera. The variables studied were as following: coverage to center back who defends the ball possessor, avoiding the gaps which wins the back, individual defense to the players who intent to pass from the back of the second center back (in-out) and eliminating the unmarked space of depth keeping the line with the center back. To analyze the information, we used the Longomatch program and the Excel with an evaluation instrument. The main results were that the Unió Esportiva Llagostera team did less errors in the execution of IBP, although this team continued having errors in the execution of these basis

Influence of Deposition Potential on Structure of ZnO Nanowires Synthesized in Track-Etched Membranes

Single-crystal ZnO nanowires long up to several microns were fabricated by one-step electrochemical deposition. A template-based process employing track-etched polycarbonate (TE-PC) membranes was used for this purpose. The morphology and the structure characteristics of the ZnO nanowires were analyzed by means of Scanning Electron Microscopy (SEM), Focused Ion Beam (FIB), Transmission Electron Microscopy (TEM), and Selected Area Electron Diffraction (SAED). The growth process conditions turned out to have a marked influence on the crystal nature and morphology of the nanowires. Deposition rates ranging from 0.4 nm s -1 and up to 0.6 nm s -1 were recorded for the growth of ZnO nanowires. The obtained results showed that by using carefully controlled deposition conditions single crystalline nanowires and fine-grained structures can be routinely obtained. © 2012 The Electrochemical Society.This work was supported by the European Commission through the program PEOPLE, by the project no. MRTN-CT-2006-035884.Pruna, AI.; Pullini, D.; Busquets Mataix, DJ. (2012). Influence of Deposition Potential on Structure of ZnO Nanowires Synthesized in Track-Etched Membranes. Journal of The Electrochemical Society. 159(4):92-98. doi:10.1149/2.003205jesS9298159

A closed circuit electro-hydraulic actuator with energy recuperation capability

The recent electrification trend in the off-road market has incentivized research towards the proposal of compact, cost-effective and energy-efficient solutions for hydraulic actuators. As a result, increased attention has been given to electro-hydraulic actuator (EHA) architectures. The paper offers a study performed on a novel closed-circuit EHA architecture with the goal to maximize the overall system efficiency while meeting or exceeding traditional off-road applications performance, thereby enabling further electrification of off-road applications. Both numerical and experimental approaches are utilized to validate the functionality of the proposed EHA circuital configuration in four quadrants. Moreover, the actuator functionality at both high and low velocities are considered, which has never been explored in the past due to the limitations on the hydraulic machine driving speed. The good match between the experimental data and the simulation results confirms the potential of the simulation model for sizing such EHA architecture for different actuator sizes, duty cycles, and performance levels

High-Efficiency Electrodeposition of Large Scale ZnO Nanorod Arrays for Thin Transparent Electrodes

In the present work an effective technique to synthesize large-scale c-axis oriented ZnO nanorod (NR) arrays is presented. The manuscript reports a single-step cathodic electrodeposition, either in aqueous and organic electrolytes, to fill up ultra-thin anodic nanoporous alumina templates. Prior to growing, self-ordered hexagonal array of cylindrical nanopores have been fabricated by anodizing Al thin films previously deposited onto ITOglass substrates. The diameter and the aspect ratio of the vertically aligned nanopores are about 60 nm and 8:1, respectively. The results of this work demonstrate that using dimethyl sulfoxide (DMSO) as an electrolyte leads to a growth more homogeneous in shape and crystallinity, and with 60 deposition efficiency - the highest by now in literature. This fact is most probably due to a better infiltration of the alumina nanopores by this electrolyte. SEM and XRD analysis were employed for the study of morphology and crystalline structure of the obtained ZnO NR. These measurements showed furthermore that ZnO nanorod arrays are uniformly embedded into the hexagonally ordered nanopores of the anodic alumina membrane. DMSO proved to be an optimal electrolyte to obtain single-crystalline ZnO NR arrays, highly transparent in visible light range (80 transmittance). © 2011 The Electrochemical Society.The authors thank for the financial support by the European Commission, DG Research through the program PEOPLE, by the project no. MRTN-CT-2006-035884.Pullini, D.; Pruna, AI.; Zanin, S.; Busquets Mataix, DJ. (2012). High-Efficiency Electrodeposition of Large Scale ZnO Nanorod Arrays for Thin Transparent Electrodes. Journal of The Electrochemical Society. 159(2):45-51. doi:10.1149/2.093202jesS4551159

Improving Electrochemical Properties of Polypyrrole Coatings by Graphene Oxide and Carbon Nanotubes

[EN] Nanostructured polypyrrole coating was applied on carbon paper via simple dip-coating and electrochemical approach. Hybridization with nanocarbon materials (graphene oxide (GO) and multi-walled carbon nanotubes (MWCNTs)) and their effect as an anchoring hybrid layer for the growth of polypyrrole towards improving electrochemical properties are studied. The loading of each component and their w/w ratio were evaluated. Fourier transform infrared spectroscopy, field emission scanning electron microscopy, and Raman spectroscopy were employed to characterize the properties of the coatings. The electrochemical properties were investigated by cyclic voltammetry. The results indicated the electrodeposition of polypyrrole is enhanced by the addition of MWCNTs to the GO layer due to the formation of a hierarchical network. The electrochemical performance of the modified electrode was shown to be highly dependent on the employed w/w ratio, reaching a capacitance value of about 40 mF cm-2 for a carbon paper substrate modified with GO:MWCNT in a w/w ratio of 1:2.5 and PPy layer deposited by cyclic voltammetry for 30 cycles. The contribution to total stored charge was found to be primary from the inner capacitance component of about 95.5% contribution.This research was founded by Romanian National Authority for Scientific Research and Innovation, CNCS -UEFISCDI (project number PN-III-P1-1.1-TE-2016-1544) and Escuela Politecnica Nacional (project number PIMI 15-09) and Secretaria de Educacion Superior, Ciencia, Tecnologia e Innovacion (SENESCYT).Rosas-Laverde, NM.; Pruna, AI.; Busquets Mataix, DJ. (2020). Improving Electrochemical Properties of Polypyrrole Coatings by Graphene Oxide and Carbon Nanotubes. Nanomaterials. 10(3). https://doi.org/10.3390/nano1003050710

Graphene Oxide-Polypyrrole Coating for Functional Ceramics

[EN] Ceramic substrates were metallized with a Ni-Mo-P electroless coating and further modified with a polypyrrole (PPy) coating by the electrodeposition method. The properties of the polypyrrole coating were studied with the addition of a graphene oxide (GO) nanomaterial prior to the electrodeposition and its reduction degree. Fourier Transform Infrared Spectroscopy, Field-Emission Scanning Electron Microscopy, Raman spectroscopy and cyclic voltammetry were employed to characterize the properties of the coatings. The results indicated the successful synthesis of conductive electrodes by the proposed approach. The electrodeposition of PPy and its charge storage properties are improved by chemically reduced GO. The surface capacitive contribution to the total stored charge was found to be dominant and increased 2-3 fold with the reduction of GO. The chemically reduced GO-modified PPy exhibits the highest capacitance of 660 F g-1 at 2 mV s-1, and shows a good cyclability of 94% after 500 charge/discharge cycles. The enclosed results indicate the use of an NiMoP electroless coating, and modification with a carbon nanomaterial and conducting polymer is a viable approach for achieving functional ceramics.Rosas-Laverde, NM.; Pruna, AI.; Busquets Mataix, DJ. (2020). Graphene Oxide-Polypyrrole Coating for Functional Ceramics. Nanomaterials. 10(6). https://doi.org/10.3390/nano1006118810