Search results for " Permanent"
showing 10 items of 144 documents
RFI: il caso studio della stazione GNSS dell’Università di Palermo
2009
La sperimentazione descritta in questo lavoro riguarda la prima parte di una ricerca, tuttora in corso, che vede coinvolti l’Agenzia Regionale Protezione Ambiente Sicilia (ARPA) e il Dipartimento di Rappresentazione dell’Università di Palermo (DIRAP), avente come tema le problematiche relative alle interferenze da radio frequenza registrate dalla stazione permanente GNSS dell’Università di Palermo. La stazione è stata materializzata nel 2006 e dal 2007 fa parte della rete di stazioni permanenti GNSS-NRTK gestita dal DIRAP, per attività di studio di ricerca. In particolare, in questo lavoro sono illustrati i test che sono stati condotti e i risultati in termini di interferenza elettomagnetic…
El administrador persona jurídica en las sociedades de capital
2017
La tesis doctoral analiza la deseabilidad de que las personas jurídicas y no sólo las personas naturales sean designadas administradoras en las sociedades de capital, posibilidad admitida expresamente por el artículo 212.1 de la Ley de Sociedades de Capital. Se trata de una práctica de gobierno corporativo adscrita a la tradición europea, que depende de una decisión de política jurídica adoptada por el legislador. La tesis estudia los efectos y aplicaciones de la administración societaria por personas jurídicas en el tráfico y evalúa las diferentes estrategias regulatorias que se presentan ante esta práctica de gobierno corporativo. En el ordenamiento jurídico español, la persona jurídica a…
Survey data on the consequences of COVID-19 and home confinement on the educational community and families in Spain
2021
[EN] This paper presents a dataset concerning the consequences of the COVID-19 pandemic and home confinement on the educational community and families, and the possibilities and opportunities for the return to schools. Data were collected through an online based cross-sectional survey between June 29, 2020 and July 12, 2020 in Spain. A total of 7,305 people who had children in their care during the COVID-19 crisis and the home-confinement period responded to the survey. The survey contained items concerning (i) socio-demographic information, (ii) conciliation of work, personal and family life during confinement, (iii) the impact of the pandemic on the respondent's family, and (iv) the respo…
The use of sea waves for generation of electrical energy: a linear tubular asynchronous electrical generator
2007
A linear tubular asynchronous generator to be used as generator driven by seawave is presented. The design criteria of a TLIM with hollowed iron induced part as well as the technological processes to be adopted and the materials utilized in the various parts are described. The methodologies for mechanical assembling and electric wiring are considered too. Finally, the prototype with bimetallic induced part that has been designed and built is presented and some experimental results on electrical and mechanical variables are shown.
A Ferrite Tubular Linear Permanent Magnet Generator (FTLPMG) analysis and design
2014
Several linear synchronous generators for the exploitation of sea wave energy have been proposed. Such machines do not require reactive power for the magnetization since they use permanent magnets for the excitation. The use of permanent magnets in a rough environment such as the marine environment may be a very weak point in the application of these kind of devices. In order to overcome this difficulty, the authors in this paper propose a linear synchronous electrical generator. Its excitation uses ferrites as suitable solutions to extract energy from sea waves. This paper describes the analysis and design of an improved axially magnetized tubular permanent-magnet machine in which several …
A new approach in the monitoring of the phytosanitary conditions of forests: the case of oak and beech stands in the Sicilian Regional Parks.
2016
The objective of this study was to investigate the health conditions of oak and beech stands in the three Regional Parks of Sicily (Etna, Madonie and Nebrodi). A total of 81 sampling areas were investigated, 54 in oak stands and 27 in beech stands. The phytosanitary conditions of each tree within the respective sampling area was expressed with a synthetic index namely phytosanitary class (PC). Oak stands showed severe symptoms of decline, with 85% of the sampling areas including symptomatic trees. In general, beech stands were in better condition, with the exception of Nebrodi Park, where trees showed severe symptoms of decline. On oak trees, infections of fungal pathogens were also observe…
Performance improvements of asphalt mixtures by dry addition of polymeric additives
2017
This paper shows the results of an experimental study concerning the development and optimization of asphalt mixtures for binder and base courses, improved with specifically engineered additives. The focus was on the mechanical improvements of the mixtures as achievable via dry modification with polymeric additives by making use of aggregate and bitumen of average quality, as locally available, in order to limit the consumption of virgin materials. The results allowed interesting conclusions to be drawn about the use of polymeric additives for these mixtures. In particular, the modified mixtures proved to have better performance in terms of both permanent deformation resistance and stiffnes…
An Experimental Comparison between an Ironless and a Traditional Permanent Magnet Linear Generator for Wave Energy Conversion
2022
Permanent Magnet Linear Generators (PMLGs) are currently being studied for sea wave energy harvesting. Typically, a PMLG consists of an iron-made armature and a moving translator. The permanent magnets adoption produces parasitic effects, such as cogging force, and the machine weight increment. A solution could be the adoption of an ironless configuration, accepting a power density reduction. This paper investigates the use of ironless PMLGs in sea wave energy conversion systems by an experimental comparative analysis between an iron PMLG prototype and an ironless PMLG prototype, which share the same geometry. The main electrical and mechanical parameters (resistance, mass, and magnetic fie…
STUDIO DI UN AMMORTIZZATORE ELETTROMAGNETICO A RECUPERO DI ENERGIA
2013
Questo lavoro ha come obiettivo principale lo studio teorico e con supporto di software F.E.M. di un dispositivo che consenta recupero energetico da una sospensione automobilistica. In sostituzione allo smorzatore viscoso, che dissipa l’energia cinetica del veicolo a seguito dell’attraversamento di strade sconnesse o ostacoli più marcati, si è usato uno smorzatore elettromagnetico che svolga le funzioni dello smorzatore viscoso consentendo un recupero di energia elettrica. Lo smorzatore elettromagnetico è di tipo a magneti permanenti e il suo funzionamento si basa sul fenomeno dell’induzione elettromagnetica. Il modello matematico descrive il funzionamento dello smorzatore, restituendo i va…
Characterization of interior permanent magnet synchronous motors for loss model algorithm identification
2016
The paper provides the results of a detailed experimental study on the variations of the characteristics of an interior permanent magnet synchronous motor, when load, speed and/or magnetization conditions vary. In particular, the characterization is carried out by assessing, for several working conditions, the motor parameters that influence its efficiency. From the knowledge of the variability of these parameters, it is possible to develop a dynamic model of the motor, which accurately describes its behaviour and allows estimating the power losses for whatever speed and load. In order to validate the model, the values of the power losses obtained by using the model are compared with the va…