On-line identification of seeds in mandarins with magnetic resonance imaging

Mandarins have been inspected using magnetic resonance imaging (MRI) in order to detect the presence of seeds. To enhance contrast between seeds and pulp, effective transverse relaxation time-weighted fast low angle shot images (703 ms acquisition time) were acquired. Stationary fruits were imaged and then the images were segmented to extract several features. The maximum radius of the region containing the seeds and the central axis rmax, and the perimeter of this region P were the most powerful features for discrimination between seedless and seed-containing fruits. Such features were the most robust since they showed the lowest noise-to-signal ratios (N/S). The proportions of correct classification were 88.9% and 86.7% for seedless and seed-containing fruits, respectively, under MRI stationary conditions. The performance under on-line conditions was evaluated by imaging the fruits while conveyed at 54 mm/s. An analysis of variance with the features extracted from the static images and the motion-corrected dynamic images showed that there were statistically indistinguishable. The proportions of correct classification were 92.5% and 79.5% for the seedless and seed-containing category, respectively, under MRI dynamic conditions. Reduction in the distance between categories for rmax was addressed as the main cause for the decrease in discrimination performance. The robustness of the motion correction procedure was highlighted by the low differences in the N/S ratio and the noise-to-measured range ratios between static and dynamic features

Papel de las bacterias del ácido láctico en verduras fermentadas

The consumption of fermented vegetables is widespread throughout the world and represents an important component of the human diet with considerable contribution to the food supply for a world popula­tion in continuous growth. Many of the fermented vegetables share a general process which requires salting and acidification steps. Among the microorganisms responsible for fermentation, lactic acid bacteria are the most relevant with important organoleptic, quality and safety benefits. This review deals with the microbial ecology of fermented vegetables focusing on the biodiversity of lactic acid bacteria, the most important molecular tech­niques used for their identification and genotyping, their importance for the formation of biofilms as well as their use as starter cultures for obtaining high-quality and safe vegetable products.El consumo de vegetales fermenta­dos está muy extendido en el mundo y representa un componente importante de la dieta humana con un apoyo considerable a la cadena alimentaria para una población mundial en continuo crecimiento. Muchos de los vege­tales fermentados comparten un proceso general, que requiere una puesta en salmuera y acidificación. Entre los microorganismos responsables de la fermentación, las bacterias del ácido láctico son las más relevantes con una importante influencia sobre aspectos organolépticos, de calidad y seguridad del producto final. Esta revisión trata sobre la ecología microbiana de los vegetales fermentados, prestando especial atención a la biodiversidad de las bacterias del ácido láctico, las técnicas moleculares más importantes utilizadas para su identificación y genotipado, su importancia para la formación de biofilms y su uso como cultivos iniciadores multifuncionales para la obtención de productos vegetales de alta calidad y seguridad

Flat plate solar collector performance using alumina nanofluids: Experimental characterization and efficiency tests

Solar energy has become an important renewable energy source for reducing the use of fossil fuels and to mitigate global warming, for which solar collectors constitute a technology that is to be promoted. The use of nanofluids can increase the efficiency of solar into thermal energy conversion in solar collectors. Experimental values for the specific heat, thermal conductivity and viscosity of alumina/water nanofluids are needed to evaluate the influence of the solid content (from 0.25 to 5 v%) and the flow rate on the Reynolds, Nusselt and the heat transfer coefficient. In the laminar flow regime, thermal conductivity enhancement over specific heat decrement is key parameter, and a 2.34% increase in the heat transfer coefficient is theoretically obtained for 1 v% alumina nanofluid. To corroborate the results, experimental tests were run in a flat plate solar collector. A reduction in efficiency from 47% to 41.5% and a decrease in the heat removal factor were obtained using the nanofluid due to the formation of a nanoparticle deposition layer adding an addition thermal resistance to heat transfer. Nanofluids are recommended only if the nanoparticle concentration is high enough to enhance thermal conductivity, but no so high so as to avoid wall deposition

Evaluación de un laboratorio web como complemento de un curso de Electrónica Básica

Ponencia presentada en el Congreso de Tecnologías Aplicadas a la Enseñanza de la Electrónica (TAEE 2004), celebrado en Valencia durante los días 14-17 de julio de 2004.Se presentan los resultados obtenidos de la experiencia docente realizada en la asignatura Electrónica de segundo curso de Ingeniería Informática en la Universidad Autónoma de Madrid. Se ha incorporado un laboratorio accesible desde Web como complemento práctico de un curso de electrónica básica. El laboratorio Web dispone de una colección básica de ejercicios prácticos de análisis de circuitos. Se proponen experimentos complementarios a la teoría que permitan a los estudiantes familiarizarse con la caracterización de dispositivos, y en los cuales, el alumno realiza medidas reales de los dispositivos electrónicos. Los resultados muestran que el interfaz desarrollado para simplificar la utilización del equipo de medida ha sido bien acogido, y en general los alumnos valoran positivamente este tipo de práctica no presencial.Este trabajo ha sido parcialmente financiado por el proyecto europeo número: 100671-CP-1- 2002-1-FR-MINERVA-M y por el proyecto 07T/0052/2003 3 de la Consejería de Educación de la Comunidad de Madri

Emerge: una red educativa europea para la integración de laboratorios accesibles via web

Ponencia presentada en el Congreso de Tecnologías Aplicadas a la Enseñanza de la Electrónica (TAEE 2004), celebrado en Valencia durante los días 14-17 de julio de 2004.El proyecto europeo Emerge propone crear una red educativa que pretende la integración de experimentos de laboratorio accesibles en remoto desde Web. El objetivo final consiste en extender la utilización de los laboratorios fuera de las instituciones individuales que forman parte del proyecto. Mediante tecnologías Web e instrumentación controlada por ordenador los estudiantes europeos tendrán a su disposición un conjunto de prácticas relacionadas con el área de la ingeniería electrónica. Para lograrlo se están desarrollando nuevas soluciones que integran los experimentos de los laboratorios de cada unos de los socios así como los servicios comunes. Se plantea cómo resolver los aspectos de seguridad, el control de acceso y el desarrollo de interfaces de usuario escalables. Las soluciones aportadas están basadas en tecnologías Web estándar como Applets, SOAP o PHP. En este trabajo se presenta el estado actual del proyecto, el material de soporte desarrollado y las prácticas que ya están accesibles desde el portal Web.Este proyecto ha sido llevado a cabo con la ayuda de la Comunidad Europea en el marco del programa Sócrates, EU Programa No: 100671-CP-1-2002-1-FR-MINERVA-

Experimental evaluation of the energy performance of an air vortex tube when the inlet parameters are varied

The paper presents the analysis of the energy performance of an air vortex cooling tube under variations of the air inlet properties, with three independent experimental tests validated through the energy balance in the device. The experimental analysis includes the following variations of the input conditions: First, the effect of the air inlet pressure to the vortex tube, focused on the analysis of temperature variations in the output cold stream and in the cooling capacity when the cold flow fraction varies. Second, we studied air inlet temperature variations to the vortex tube under different cold flow fractions, which is an analysis not found in the literature. And finally, is studied the performance of the vortex tube when the insulation is provided or in absence of insulation.Torrella Alcaraz, E.; Patiño, J.; Sánchez, D.; Llopis, R.; Cabello, R. (2013). Experimental evaluation of the energy performance of an air vortex tube when the inlet parameters are varied. Open Mechanical Engineering Journal. 7(1):98-107. doi:10.2174/1874155X01307010098S981077

Spatial distribution and statistical properties of small-scale convective vortex-like motions in a quiet Sun region

High-resolution observations of a quiet Sun internetwork region taken with the Solar 1-m Swedish Telescope in La Palma are analyzed. We determine the location of small-scale vortex motions in the solar photospheric region by computing the horizontal proper motions of small-scale structures on time series of images. These plasma convectively-driven swirl motions are associated to: (1) downdrafts (that have been commonly explained as corresponding to sites where the plasma is cooled down and hence returned to the interior below the visible photospheric level), and (2) horizontal velocity vectors converging into a central point. The sink cores are proved to be the final destination of passive floats tracing plasma flows towards the center of each vortex. We establish the occurrence of these events to be 1.4 x 10^(-3) and 1.6 x 10^(-3) vortices Mm^(-2) min^(-1) respectively for two time series analyzed here.Comment: 8 pages, 6 figures. Accepted for publication in Monthly Notices of the Royal Astronomical Societ

Spectra of weighted algebras of holomorphic functions

We consider weighted algebras of holomorphic functions on a Banach space. We determine conditions on a family of weights that assure that the corresponding weighted space is an algebra or has polynomial Schauder decompositions. We study the spectra of weighted algebras and endow them with an analytic structure. We also deal with composition operators and algebra homomorphisms, in particular to investigate how their induced mappings act on the analytic structure of the spectrum. Moreover, a Banach-Stone type question is addressed.Comment: 25 pages Corrected typo

Demo: Results of 'iCaveats', a Project on the Integration of Architectures and Components for Embedded Vision

iCaveats is a Project on the integration of components and architectures for embedded vision in transport and security applications. A compact and efficient implementation of autonomous vision systems is difficult to be accomplished by using the conventional image processing chain. In this project we have targeted alternative approaches, that exploit the inherent parallelism in the visual stimulus, and hierarchical multilevel optimization. A set of demos showcase the advances at sensor level, in adapted architectures for signal processing and in power management and energy harvesting.Ministerio de Economia, Industria y Competitividad de España (MINECO) y el Fondo Europeo de Desarrollo de las Regiones (FEDER)-‘iCaveats’ TEC2015-66878-C3-1-R, TEC2015-66878-C3-2-R y TEC2015-66878-C3-3-RJunta de Andalucía-‘SmartCIS3D’ TIC 2338-2013FEDER- 2016-2019, ED431G/08 y 2017-2020, ED431C 2017/69Agencia Ejecutiva Europea de Investigación (EU-REA)-‘Achieve’ H2020 MSCAITN 2017 N° 76586