106 research outputs found
Performance optimization in switched reluctance motor drives
In this paper, switched reluctance motors (SRM) are proposed as an alternative for electric power assisted steering (EPAS) applications. A prototype machine has been developed as very attractive design for a steering electric motor, both from a cost and size perspective. A fourphase 8/6 SRM drive is designed for a rack type EPAS which should provide a maximum force of 10 kN. Two-dimension finite element analysis is used to validate the design
Modelling and Simulation of Moored Devices for Ocean Currents Energy Harnessing
The main objective of this paper is the presentation of modelling solutions off loating devices that can be used for harnessing energy from ocean currents. It has been structured into three main parts. First, the growing current interest in marine renewable energy in general, and in extracting energy from currents in particular, is presented, showing the large number of solutions that are emerging and some of the most significant types. GESMEY generator is presented in second section. It is based on a new concept that has been patented by the Universidad Politécnica de Madrid and which is currently being developed through a collaborative agreement with the SOERMAR Foundation. The main feature of this generator is that on operation is fully submerged, and no other facilities are required to move to floating state for maintenance, which greatly increases its performance. Third part of the article is devoted to present the modelling and simulation challenges that arise in the development of devices for harnessing the energy of marine currents, along with some solutions which have been adopted within the frame of the GESMEY Project, making particular emphasis on the dynamics of the generator and its contro
Dispositivo para aprovechar la energía de corrientes marinas
En este articulo se expone el proceso seguido en la definición y desarrollo de un generador, denominado GESMEY, para el aprovechamiento de la energía de las corrientes marinas situadas a más de 40 metros de profundidad, lo que junto a sus características definitorias que le permiten evolucionar en el seno marino sólo utilizando fuerzas hidrodinámicas, le definen como un dispositivo con mejores prestaciones que los existentes a la fecha. Por ello puede afirmarse que GESMEY es ya un dispositivo perteneciente a una segunda generación de convertidores
Control architecture of a prototype for the real-time validation of emersion and immersion maneuvers of underwater devices for energy harnessing
The exploitation of renewable marine energy sources requires devices
which have been proven to be economically competitive with regard to other traditional
energy sources. One of the current study aims is to reduce maintenance
costs by successively automating more tasks. It is necessary to design and build
laboratory prototypes in order to validate both the dynamic model and the control
algorithms for the automatic emersion (depth to the sea surface) and immersion
(from the sea surface to the depth of operation) maneuvers of devices with which to
harness renewable energies.
This paper presents the instrumentation and control architecture of a reduced scale
prototype that was conceived for experimentation in a calm water basin.Peer Reviewe
Nano-second laser interference photoembossed microstructures for enhanced cell alignment
Photoembossing is a powerful photolithographic technique to prepare surface relief structures relying on polymerization-induced diffusion in a solventless development step. Conveniently, surface patterns are formed by two or more interfering laser beams without the need for a lithographic mask. The use of nanosecond pulsed light-based interference lithography strengthens the pattern resolution through the absence of vibrational line pattern distortions. Typically, a conventional photoembossing protocol consists of an exposure step at room temperature that is followed by a thermal development step at high temperature. In this work, we explore the possibility to perform the pulsed holographic exposure directly at the development temperature. The surface relief structures generated using this modified photoembossing protocol are compared with those generated using the conventional one. Importantly, the enhancement of surface relief height has been observed by exposing the samples directly at the development temperature, reaching approximately double relief heights when compared to samples obtained using the conventional protocol. Advantageously, the light dose needed to reach the optimum height and the amount of photoinitiator can be substantially reduced in this modified protocol, demonstrating it to be a more efficient process for surface relief generation in photopolymers. Kidney epithelial cell alignment studies on substrates with relief-height optimized structures generated using the two described protocols demonstrate improved cell alignment in samples generated with exposure directly at the development temperature, highlighting the relevance of the height enhancement reached by this method. Although cell alignment is well-known to be enhanced by increasing the relief height of the polymeric grating, our work demonstrates nano-second laser interference photoembossing as a powerful tool to easily prepare polymeric gratings with tunable topography in the range of interest for fundamental cell alignment studies
Baseline Characteristics from UNITE: An Observational, International, Multicentre Registry to Evaluate Hidradenitis Suppurativa (Acne Inversa) in Clinical Practice
Background: Hidradenitis suppurativa (HS), also known as acne inversa, is a recurring, painful, chronic, and sometimes disfiguring inflammatory skin disease. Objectives: Our objective was to report the baseline clinical characteristics, natural history, and associated outcomes of patients with HS from the ongoing, prospective, non-interventional UNITE registry that is collecting data regarding the natural history and associated outcomes of HS. Methods: Patients with inflammatory HS lesions were enrolled, including adolescents (aged 12 to < 18 years) and adults (aged ≥ 18 years). None had participated in previous or current originator-adalimumab studies/registries. Patients received treatment consistent with site-specific, routine clinical practice. HS disease status was assessed by HS lesions and disease flare; treatment and outcomes data were collected at e
Propuesta para la Reestructuración Funcional de la Figura del Coordinador de Virtualización en la UNED
El sistema organizativo académico de la Universidad Nacional de Educación a Distancia (UNED) está integrado por docentes en la Sede Central y profesores tutores en los Centros Asociados repartidos por el territorio español. A partir del nuevo panorama educativo en la enseñanza universitaria europea (Espacio Europeo de Enseñanza Superior, -EEES), la UNED se fue adaptando y situándose en un escenario moderno e innovador, iniciándose la mejora y homogeneización de los servicios que reciben los estudiantes mediante los cursos virtuales. En este contexto, se precisó la formación a profesores tutores y a estudiantes en la utilización de los cursos virtuales de la universidad, surgiendo así el rol del Coordinador de Virtualización (CV). En la actualidad hay 62 coordinadores (uno por cada centro asociado). Tras la implantación de las nuevas titulaciones dentro del marco del EEES y, una vez consolidada esta figura en la institución, se ha hecho necesario ofrecer una nueva organización en las funciones y tareas que los CV han de ejercer. Este trabajo describe la nueva propuesta organizativa diseñada para su aplicación a partir del próximo curso 2014-2015, y para cuya elaboración se han seguido los siguientes pasos: identificación del tipo de tareas a desarrollar (apoyo tecnológico a estudiantes y asesoramiento a profesores tutores), establecimiento de los contextos de trabajo (presencial y virtual), y clasificación por categorías para permitir una asignación de actividades básicas a todos los CV y de actividades más especializadas entre subgrupos de CV. Palabras llave: Aprendizaje semipresencial; Formación de profesorado; Competencias tecnológicas; Habilidades digitales. Virtualization Coordinator: Trainer of Tutor-Professors and Support for Students in the UNED Associate CenterAbstract The academic organizational structure of the Universidad Nacional de Educación a Distancia (UNED) is composed of professors at Central Headquarters and tutor-professors at the Associate Centers spread across the Spanish territory. From the new educational landscape in European university education (European Higher Education Area - EHEA), UNED was adapting and placing itself in a modern and innovative stage, beginning with the improvement and standardization of services provided to students through the online courses. In this context, training for both tutor-professors and students in the use of online courses was required, and that´s how the role of Virtualization Coordinator (VC) emerged. At present time, there are 66 VCs (one for each Associate Center). After implementation of the new qualifications within the framework of the EHEA and once established this role in the institution, it is necessary to provide a new organization in the functions and tasks that have to exercise VC. This paper describes a new organizational proposal designed for use from next year 2014-2015, and to whose development we have followed the following steps: identification of the type of tasks to be performed (technical support to students and advice to tutor-professors), establishment of working contexts (presential and virtual), and categorization to allow distribution of basic activities among all the VC, and more specialized activities among subgroups of VC.Keywords: Blended learning; Teachers training; Technological competences; Digital skills
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